Set version to 1.5.3

Added overloading methods for easier access

Database-Attribute_System/Attributes/DbForeignObject.cs

@@ -26,14 +26,15 @@ namespace eu.railduction.netcore.dll.Database_Attribute_System.Attributes
             this._foreignKeyName = foreignKeyName;
         }
 
-        public void Init(FieldInfo fi, DbObject classAttribute)
+        public void Init(FieldInfo fi, DbObject classAttribute, DbObject foreignClassAttribute = null)
         {
             this.parentField = fi;
             this.classAttribute = classAttribute;
             this.foreignObjectType = fi.FieldType;
 
             // Init foreign-object class
-            DbObject foreignClassAttribute = ClassAction.Init(this.foreignObjectType);
+            if(foreignClassAttribute == null)
+                foreignClassAttribute = ClassAction.Init(this.foreignObjectType);
 
             // Check if something is weird
             if (foreignClassAttribute.primaryKeyAttributes.Count < 1) throw new InvalidOperationException($"'{foreignClassAttribute.parentClassType.Name}' does not have a primaryKey.");

Database-Attribute_System/Attributes/DbIntermediateForeignObject.cs

@@ -0,0 +1,78 @@
+using System;
+using System.Collections;
+using System.Collections.Generic;
+using System.Linq;
+using System.Reflection;
+using System.Threading.Tasks;
+
+namespace eu.railduction.netcore.dll.Database_Attribute_System.Attributes
+{
+    [AttributeUsage(AttributeTargets.Field, Inherited = false, AllowMultiple = false)]
+    public class DbIntermediateForeignObject : Attribute
+    {
+        public Type foreignObjectType;
+
+        public string _intermediateTableName;
+
+        public string _keyName;
+        public string _foreignKeyName;
+
+
+        public DbPrimaryKey foreignPrimaryKeyAttribute;
+
+        public FieldInfo parentField;
+        public DbObject classAttribute;
+
+        /// <summary>
+        /// Marks variable as intermediate-object of an dbObject
+        /// </summary>
+        /// <param name="intermediateTableName">Table-name of intermediate-table. Must contain primaryKey of this class & target class</param>
+        /// <param name="keyName">Fieldname of primaryKey associated with the IntermediateObject on this side [m]:n (null if same as primary key) [Only works with 1 primaryKey]</param>
+        /// <param name="foreignKeyName">Fieldname of primaryKey associated with the IntermediateObject on the other side m:[n] (null if same as primary key) [Only works with 1 primaryKey]</param>
+        public DbIntermediateForeignObject(string intermediateTableName, string keyName = null, string foreignKeyName = null)
+        {
+            this._intermediateTableName = intermediateTableName;
+            this._foreignKeyName = foreignKeyName;
+        }
+
+        public void Init(FieldInfo fi, DbObject classAttribute)
+        {
+            this.parentField = fi;
+            this.classAttribute = classAttribute;
+            this.foreignObjectType = fi.FieldType;
+
+            if (classAttribute.primaryKeyAttributes.Count < 1) throw new InvalidOperationException($"'{classAttribute.parentClassType.Name}' does not have a primaryKey.");
+            if (classAttribute.primaryKeyAttributes.Count > 1) throw new InvalidOperationException($"IntermediateObject does not support multiple primaryKeys.");
+            // Get primaryKey name if none is set
+            if (_keyName == null) _keyName = classAttribute.primaryKeyAttributes[0]._attributeName;
+
+            if (!(fi.FieldType.IsGenericType && (fi.FieldType.GetGenericTypeDefinition() == typeof(List<>))))  // 1:m
+                throw new InvalidOperationException($"IntermediateObject has to be typeof(List<T>). Maybe you meant to use DbForeignObject or DbReverseForeignObject for 1:m or 1:1 relations.");
+
+            // Check the generic list and get inner-type
+            Type foreignObjectType = null;
+            foreach (Type interfaceType in fi.FieldType.GetInterfaces())
+            {
+                if (interfaceType.IsGenericType &&
+                    interfaceType.GetGenericTypeDefinition()
+                    == typeof(IList<>))
+                {
+                    foreignObjectType = fi.FieldType.GetGenericArguments()[0];
+                    break;
+                }
+            }
+            if (foreignObjectType == null) throw new InvalidOperationException("Could not read innter-type of generic-list!");
+
+            // Init inner-type class
+            DbObject foreignClassAttribute = ClassAction.Init(foreignObjectType);
+
+            // Check the primaryKey/s
+            if (foreignClassAttribute.primaryKeyAttributes.Count < 1) throw new InvalidOperationException($"'{foreignClassAttribute.parentClassType.Name}' does not have a primaryKey.");
+            if (foreignClassAttribute.primaryKeyAttributes.Count > 1) throw new InvalidOperationException($"IntermediateObject does not support multiple primaryKeys. (Found '{foreignClassAttribute.primaryKeyAttributes.Count}' in '{foreignClassAttribute.parentClassType.Name}')");
+            // Save it
+            foreignPrimaryKeyAttribute = foreignClassAttribute.primaryKeyAttributes[0];
+
+            if (_foreignKeyName == null) _foreignKeyName = foreignPrimaryKeyAttribute._attributeName;
+        }
+    }
+}

Database-Attribute_System/Attributes/DbObject.cs

@@ -13,6 +13,7 @@ namespace eu.railduction.netcore.dll.Database_Attribute_System.Attributes
         public string _tableName;
 
         public Type parentClassType;
+        public ConstructorInfo parentCInfo;
 
         // All childrenAttributes
         public List<BaseAttribute> baseAttributes = new List<BaseAttribute>() { };
@@ -20,6 +21,8 @@ namespace eu.railduction.netcore.dll.Database_Attribute_System.Attributes
         public List<DbAttribute> attributeAttributes = new List<DbAttribute>() { };
         public List<DbForeignKey> foreignKeyAttributes = new List<DbForeignKey>() { };
         public List<DbForeignObject> foreignObjectAttributes = new List<DbForeignObject>() { };
+        public List<DbReverseForeignObject> reverseForeignObjectAttributes = new List<DbReverseForeignObject>() { };
+        public List<DbIntermediateForeignObject> intermediateObjectAttributes = new List<DbIntermediateForeignObject>() { };
 
         /// <summary>
         /// Marks variable as database-table
@@ -33,6 +36,8 @@ namespace eu.railduction.netcore.dll.Database_Attribute_System.Attributes
         public void Init(Type classType)
         {
             this.parentClassType = classType;
+            parentCInfo = classType.GetConstructor(Type.EmptyTypes);
+
             this._tableName = this._tableName ?? classType.Name;    // If no alternative table-name is specified, use the class-name
 
             // Iterate thru all fields
@@ -64,10 +69,23 @@ namespace eu.railduction.netcore.dll.Database_Attribute_System.Attributes
                     }
                     else if (fi.GetCustomAttribute(typeof(DbForeignObject), true) is DbForeignObject fobj)    // ForeignObjects
                     {
-                        fobj.Init(fi, this);
+                        if(fi.FieldType == this.parentClassType)    // Check if we are referencing ourselfes
+                            fobj.Init(fi, this, this);
+                        else
+                            fobj.Init(fi, this);
 
                         this.foreignObjectAttributes.Add(fobj);
                     }
+                    else if (fi.GetCustomAttribute(typeof(DbReverseForeignObject), true) is DbReverseForeignObject rfobj)    // ReverseForeignObjects
+                    {
+                        rfobj.Init(fi, this);
+                        this.reverseForeignObjectAttributes.Add(rfobj);
+                    }
+                    else if (fi.GetCustomAttribute(typeof(DbIntermediateForeignObject), true) is DbIntermediateForeignObject iobj)    // ReverseForeignObjects
+                    {
+                        iobj.Init(fi, this);
+                        this.intermediateObjectAttributes.Add(iobj);
+                    }
                 }
                 catch(InvalidOperationException ex)
                 {

Database-Attribute_System/Attributes/DbReverseForeignObject.cs

@@ -0,0 +1,77 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Reflection;
+using System.Threading.Tasks;
+
+namespace eu.railduction.netcore.dll.Database_Attribute_System.Attributes
+{
+    [AttributeUsage(AttributeTargets.Field, Inherited = false, AllowMultiple = false)]
+    public class DbReverseForeignObject : Attribute
+    {
+        public Type foreignObjectType;
+
+        public string _foreignKeyName;
+        public DbForeignKey foreignKeyAttribute;
+
+        public FieldInfo parentField;
+        public DbObject classAttribute;
+
+        /// <summary>
+        /// Marks variable as reverse-foreign-object of an dbObject
+        /// </summary>
+        /// <param name="foreignKeyName">Fieldname of primaryKey associated with the reverseForeignObject (null if same as primary key) [Only works with 1 primaryKey]</param>
+        public DbReverseForeignObject(string foreignKeyName = null)
+        {
+            this._foreignKeyName = foreignKeyName;
+        }
+
+        public void Init(FieldInfo fi, DbObject classAttribute)
+        {
+            this.parentField = fi;
+            this.classAttribute = classAttribute;
+            this.foreignObjectType = fi.FieldType;
+
+            if (classAttribute.primaryKeyAttributes.Count < 1) throw new InvalidOperationException($"'{classAttribute.parentClassType.Name}' does not have a primaryKey.");
+            if (classAttribute.primaryKeyAttributes.Count > 1) throw new InvalidOperationException($"ReverseForeignObject does not support multiple primaryKeys.");
+            // Get primaryKey name if none is set
+            if (_foreignKeyName == null) _foreignKeyName = classAttribute.primaryKeyAttributes[0]._attributeName;
+
+            // If its a List, get inner type
+            if (fi.FieldType.IsGenericType && (fi.FieldType.GetGenericTypeDefinition() == typeof(List<>)))
+            {
+                // Check the generic list and get inner-type
+                foreach (Type interfaceType in fi.FieldType.GetInterfaces())
+                {
+                    if (interfaceType.IsGenericType &&
+                        interfaceType.GetGenericTypeDefinition()
+                        == typeof(IList<>))
+                    {
+                        foreignObjectType = fi.FieldType.GetGenericArguments()[0];
+                        break;
+                    }
+                }
+                if (foreignObjectType == null) throw new InvalidOperationException("Could not read innter-type of generic-list!");
+            }
+
+            // Init inner-type class
+            DbObject foreignClassAttribute = ClassAction.Init(foreignObjectType);
+
+            // Check if my primary-key is set in the foreign-class as foreignKey
+            DbPrimaryKey primaryKey = classAttribute.primaryKeyAttributes[0];
+            foreach (DbForeignKey foreignKey in foreignClassAttribute.foreignKeyAttributes)
+            {
+                if (primaryKey._attributeName.ToLower() == foreignKey._attributeName.ToLower())  // Name matches
+                    if (primaryKey.parentField.GetType() == foreignKey.parentField.GetType())   // Type matches
+                    {
+                        foreignKeyAttribute = foreignKey;
+                    }
+                    else
+                        // Same name, but wrong type
+                        throw new InvalidOperationException($"ForeignObject='{foreignClassAttribute.parentClassType.Name}' has invalid type foreignKey='{foreignKey.parentField.Name}' for object='{classAttribute.parentClassType.Name}' with primaryKey='{primaryKey.parentField.Name}'.");
+            }
+            // No match
+            if (foreignKeyAttribute == null) throw new InvalidOperationException($"ForeignObject='{foreignClassAttribute.parentClassType.Name}' is missing foreignKey for object='{classAttribute.parentClassType.Name}' with primaryKey='{primaryKey.parentField.Name}'.");
+        }
+    }
+}

Database-Attribute_System/ClassAction.cs

@@ -1,5 +1,6 @@
 using eu.railduction.netcore.dll.Database_Attribute_System.Attributes;
 using System;
+using System.Collections;
 using System.Collections.Generic;
 using System.Reflection;
 using System.Text;
@@ -26,8 +27,8 @@ namespace eu.railduction.netcore.dll.Database_Attribute_System
                 // Check if given class is marked as dbObject
                 if (!(classType.GetCustomAttribute(typeof(DbObject), true) is DbObject dbObject)) throw new InvalidOperationException($"Cannot init '{classType.Name}'. Missing Attribute 'DbObject'");
 
-                dbObject.Init(classType);   // Init dbObject
                 initiatedClassTypes.Add(classType, dbObject);     // Set it to the list
+                dbObject.Init(classType);   // Init dbObject
 
                 cachedDbObject = dbObject;
             }
@@ -35,7 +36,6 @@ namespace eu.railduction.netcore.dll.Database_Attribute_System
             return cachedDbObject;
         }
 
-
         /// <summary>
         /// Fills an given dbObject with given data<para/>
         /// Data-attribute-names and class-fieldNames have to match! (non case-sensitive)
@@ -43,7 +43,21 @@ namespace eu.railduction.netcore.dll.Database_Attribute_System
         /// <typeparam name="T"></typeparam>
         /// <param name="classObject">Given object (marked with Db-attributes)</param>
         /// <param name="data">The data</param>
-        /// <param name="runDataLossChecks">This checks if any class-field and data-attribute does not exists in either (Slower)</param>
+        /// <param name="key">Key-name of data</param>
+        public static void FillObject<T>(T classObject, string key, object data)
+        {
+            Dictionary<string, object> dicData = new Dictionary<string, object>();
+            dicData.Add(key, data);
+            FillObject<T>(classObject, dicData);
+        }
+        /// <summary>
+        /// Fills an given dbObject with given data<para/>
+        /// Data-attribute-names and class-fieldNames have to match! (non case-sensitive)
+        /// </summary>
+        /// <typeparam name="T"></typeparam>
+        /// <param name="classObject">Given object (marked with Db-attributes)</param>
+        /// <param name="data">The data</param>
+        /// <param name="key">Key-name of data</param>
         public static void FillObject<T>(T classObject, Dictionary<string, object> data)
         {
             Type classType = classObject.GetType();
@@ -54,19 +68,34 @@ namespace eu.railduction.netcore.dll.Database_Attribute_System
             // Iterate through data
             foreach (KeyValuePair<string, object> data_keySet in data)
             {
+                bool dataMatchFound = false;
+
                 // Interate through class-fields
                 foreach (BaseAttribute baseAttribute in dbObject.baseAttributes)
-                { 
+                {
+                    // Remove any leading dots and table-specifiers
+                    string dbAttName = data_keySet.Key;
+                    if (dbAttName.Contains("."))
+                    {
+                        string[] dbAttNameSplit = dbAttName.Split('.');     // Split at the '.'
+                        dbAttName = dbAttNameSplit[dbAttNameSplit.Length - 1];  // Copy the ending text
+                    }
+
                     // If its a match, set the value
                     if (baseAttribute._attributeName.ToLower() == data_keySet.Key.ToLower())
                     {
                         object value = data_keySet.Value;
-                        if (baseAttribute.parentField.FieldType == typeof(Guid)) value = new Guid((string)value);   // If its a guid, i need to convert
+                        if (!(value is DBNull))     // Check if value is empty
+                        {
+                            baseAttribute.parentField.SetValue(classObject, value);
+                        }
 
-                        baseAttribute.parentField.SetValue(classObject, value);
+                        dataMatchFound = true;
                         break;
                     }
                 }
+
+                if (!dataMatchFound) throw new InvalidOperationException($"Attribute '{data_keySet.Key}' has no match in object '{classObject.GetType().Name}'");
             }
         }
 
@@ -75,15 +104,30 @@ namespace eu.railduction.netcore.dll.Database_Attribute_System
         /// Gets an dbObject by primaryKey/s
         /// </summary>
         /// <typeparam name="T"></typeparam>
-        /// <param name="classObject">Given object (marked with Db-attributes)</param>
+        /// <param name="classType">The classType (marked with Db-attributes)</param>
-        /// <param name="queryExecutor">Function to handle query-calls - Has to return Dictionary[attributeName, attributeValue]</param>
+        /// <param name="primaryKeyName">Name of the primaryKey</param>
+        /// <param name="primaryKeyValue">Value of the primaryKey</param>
+        /// <param name="primaryKeyData">KeyData of multiple primaryKeys</param>
+        /// <param name="queryExecutor">Function to handle query-calls</param>
         public static T GetByPrimaryKey<T>(Type classType, object primaryKeyValue, Func<string, List<Dictionary<string, object>>> queryExecutor) where T : new()
         {
-            Dictionary<string, object> primaryKeyData = new Dictionary<string, object>() { };
+            // Read dbObject-attribute
-            primaryKeyData.Add(null, primaryKeyValue);
+            DbObject dbObject = ClassAction.Init(classType);
 
-            return GetByPrimaryKey<T>(classType, primaryKeyData, queryExecutor);
+            if (dbObject.primaryKeyAttributes.Count < 1) throw new InvalidOperationException($"No primaryKey found in '{classType.Name}'");
+            if (dbObject.primaryKeyAttributes.Count > 1) throw new InvalidOperationException($"This 'GetByPrimaryKey' method only supports 1 primaryKey ('{dbObject.primaryKeyAttributes.Count}' found in '{classType.Name}')");
+
+            return GetByPrimaryKey<T>(classType, dbObject.primaryKeyAttributes[0]._attributeName, primaryKeyValue, queryExecutor);
         }
+        /// <summary>
+        /// Gets an dbObject by primaryKey/s
+        /// </summary>
+        /// <typeparam name="T"></typeparam>
+        /// <param name="classType">The classType (marked with Db-attributes)</param>
+        /// <param name="primaryKeyName">Name of the primaryKey</param>
+        /// <param name="primaryKeyValue">Value of the primaryKey</param>
+        /// <param name="primaryKeyData">KeyData of multiple primaryKeys</param>
+        /// <param name="queryExecutor">Function to handle query-calls</param>
         public static T GetByPrimaryKey<T>(Type classType, string primaryKeyName, object primaryKeyValue, Func<string, List<Dictionary<string, object>>> queryExecutor) where T : new()
         {
             Dictionary<string, object> primaryKeyData = new Dictionary<string, object>() { };
@@ -91,14 +135,25 @@ namespace eu.railduction.netcore.dll.Database_Attribute_System
 
             return GetByPrimaryKey<T>(classType, primaryKeyData, queryExecutor);
         }
+        /// <summary>
+        /// Gets an dbObject by primaryKey/s
+        /// </summary>
+        /// <typeparam name="T"></typeparam>
+        /// <param name="classType">The classType (marked with Db-attributes)</param>
+        /// <param name="primaryKeyName">Name of the primaryKey</param>
+        /// <param name="primaryKeyValue">Value of the primaryKey</param>
+        /// <param name="primaryKeyData">KeyData of multiple primaryKeys</param>
+        /// <param name="queryExecutor">Function to handle query-calls</param>
         public static T GetByPrimaryKey<T>(Type classType, Dictionary<string, object> primaryKeyData, Func<string, List<Dictionary<string, object>>> queryExecutor) where T: new()
         {
-            // Create new empty object
-            T obj = new T();
-
             // Read dbObject-attribute
             DbObject dbObject = ClassAction.Init(classType);
 
+            if (dbObject.primaryKeyAttributes.Count < 1) throw new InvalidOperationException($"No primaryKey found in '{classType.Name}'");
+
+            // Create new empty object
+            T obj = (T)dbObject.parentCInfo.Invoke(null);
+
             // iterate thru them to check and fill object
             foreach (DbPrimaryKey primaryKeyAtt in dbObject.primaryKeyAttributes)
             {
@@ -119,11 +174,18 @@ namespace eu.railduction.netcore.dll.Database_Attribute_System
                 }
 
                 // If no data was found matching this field
-                if (!dataMatchFound) throw new InvalidOperationException($"Cannot create object with primaryKeyData. No data assigned to field '{primaryKeyAtt.parentField.Name}'");
+                if (!dataMatchFound) throw new InvalidOperationException($"PrimaryKey='{primaryKeyAtt.parentField.Name}' is missing.");
             }
 
-            ResolveByPrimaryKey<T>(obj, queryExecutor);
+            try
-
+            {
+                ResolveByPrimaryKey<T>(obj, queryExecutor);
+            }catch(InvalidOperationException)
+            {
+                // If there is no result, return null
+                return default(T);
+            }
+            
             return obj;
         }
 
@@ -134,7 +196,7 @@ namespace eu.railduction.netcore.dll.Database_Attribute_System
         /// </summary>
         /// <typeparam name="T"></typeparam>
         /// <param name="classObject">Given object (marked with Db-attributes)</param>
-        /// <param name="queryExecutor">Function to handle query-calls - Has to return Dictionary[attributeName, attributeValue]</param>
+        /// <param name="queryExecutor">Function to handle query-calls</param>
         public static List<T> GetList<T>(Type classType, Func<string, List<Dictionary<string, object>>> queryExecutor) where T : new()
         {
             // Read dbObject - attribute
@@ -155,12 +217,41 @@ namespace eu.railduction.netcore.dll.Database_Attribute_System
         }
 
         /// <summary>
-        /// Gets an dbObject by primaryKey/s
+        /// Gets a list of dbObjects by attribute/s
+        /// </summary>
+        /// <typeparam name="T"></typeparam>
+        /// <param name="classType">Type of class</param>
+        /// <param name="fields">class-fields for select</param>
+        /// <param name="queryExecutor">Function to handle query-calls</param>
+        /// <returns>List of dbObjects</returns>
+        public static List<T> GetListByAttribute<T>(Type classType, Dictionary<string, object> fields, Func<string, List<Dictionary<string, object>>> queryExecutor) where T : new()
+        {
+            // Read dbObject-attribute
+            DbObject dbObject = ClassAction.Init(classType);
+
+            Function.ConvertAttributeToDbAttributes(classType, fields);
+
+            string query = QueryBuilder.SelectByAttribute(dbObject._tableName, fields);   // Generate query
+            List<Dictionary<string, object>> dataSet = queryExecutor(query);    // Execute
+
+            List<T> objs = new List<T>() { };
+            foreach (Dictionary<string, object> data in dataSet)
+            {
+                T obj = new T();    // New object
+                FillObject(obj, data);   // Fill it
+                objs.Add(obj);      // Add to list
+            }
+
+            return objs;    // Return list
+        }
+
+        /// <summary>
+        /// Gets an dbObject by custom where-clause
         /// </summary>
         /// <typeparam name="T"></typeparam>
         /// <param name="classObject">Given object (marked with Db-attributes)</param>
         /// <param name="whereClause">Custom where-clause params attached to query (SELECT * FROM tableName WHERE whereClause)</param>
-        /// <param name="queryExecutor">Function to handle query-calls - Has to return Dictionary[attributeName, attributeValue]</param>
+        /// <param name="queryExecutor">Function to handle query-calls</param>
         public static List<T> GetListWithWhere<T>(Type classType, Func<string, List<Dictionary<string, object>>> queryExecutor, params object[] whereClause) where T : new()
         {
             // Read dbObject - attribute
@@ -179,28 +270,24 @@ namespace eu.railduction.netcore.dll.Database_Attribute_System
 
             return objs;    // Return list
         }
-        
+
         /// <summary>
-        /// Gets a list of dbObjects by attribute/s
+        /// Gets an dbObject by full query
         /// </summary>
         /// <typeparam name="T"></typeparam>
-        /// <param name="classType">Type of class</param>
+        /// <param name="classObject">Given object (marked with Db-attributes)</param>
-        /// <param name="fields">class-fields for select</param>
+        /// <param name="customQuery">Custom sql-query</param>
-        /// <param name="queryExecutor">Function to handle query-calls - Has to return Dictionary[attributeName, attributeValue]</param>
+        /// <param name="queryExecutor">Function to handle query-calls</param>
-        /// <param name="runDataLossChecks">This checks if any class-field and data-attribute does not exists in either (Slower)</param>
+        public static List<T> GetListWithQuery<T>(Type classType, Func<string, List<Dictionary<string, object>>> queryExecutor, params object[] customQuery) where T : new()
-        /// <returns>List of dbObjects</returns>
-        public static List<T> GetListByAttribute<T>(Type classType, Dictionary<string, object> fields, Func<string, List<Dictionary<string, object>>> queryExecutor) where T : new()
         {
-            // Read dbObject-attribute
+            // Read dbObject - attribute
             DbObject dbObject = ClassAction.Init(classType);
 
-            Function.ConvertAttributeToDbAttributes(classType, fields);
+            string query = QueryBuilder.BuildQuery(customQuery);
-
-            string query = QueryBuilder.SelectByAttribute(dbObject._tableName, fields);   // Generate query
             List<Dictionary<string, object>> dataSet = queryExecutor(query);    // Execute
 
             List<T> objs = new List<T>() { };
-            foreach(Dictionary<string, object> data in dataSet)
+            foreach (Dictionary<string, object> data in dataSet)
             {
                 T obj = new T();    // New object
                 FillObject(obj, data);   // Fill it
@@ -218,12 +305,17 @@ namespace eu.railduction.netcore.dll.Database_Attribute_System
         /// </summary>
         /// <typeparam name="T"></typeparam>
         /// <param name="classObject">Given object (marked with Db-attributes)</param>
-        /// <param name="queryExecutor">Function to handle query-calls - Has to return Dictionary[attributeName, attributeValue]</param>
+        /// <param name="queryExecutor">Function to handle query-calls</param>
-        public static void ResolveByPrimaryKey<T>(T classObject, Func<string, List<Dictionary<string, object>>> queryExecutor)
+        public static void ResolveByPrimaryKey<T>(T classObject, Func<string, List<Dictionary<string, object>>> queryExecutor, bool throwExceptions = true)
         {
             string query = QueryBuilder.SelectByPrimaryKey(classObject);   // Generate query
             List<Dictionary<string, object>> dataSet = queryExecutor(query);    // Execute
-            FillObject(classObject, dataSet[0]);   // Fill the object
+
+            if (dataSet.Count == 0)
+            {
+                if (throwExceptions) throw new InvalidOperationException($"Cannot fetch '{typeof(T).Name}' by primary key/s. No results!");
+            }
+            else FillObject(classObject, dataSet[0]);   // Fill the object
         }
 
         /// <summary>
@@ -232,9 +324,8 @@ namespace eu.railduction.netcore.dll.Database_Attribute_System
         /// </summary>
         /// <typeparam name="T"></typeparam>
         /// <param name="classObject">Given object (marked with Db-attributes)</param>
-        /// <param name="queryExecutor">Function to handle query-calls - Has to return Dictionary[attributeName, attributeValue]</param>
+        /// <param name="queryExecutor">Function to handle query-calls</param>
         /// <param name="max_depth">Determents how deep resolving will be executed</param>
-        /// <param name="runDataLossChecks">This checks if any class-field and data-attribute does not exists in either (Slower)</param>
         public static void ResolveForeignKeys<T>(T classObject, Func<string, List<Dictionary<string, object>>> queryExecutor, int max_depth = 1) where T: new()
         {
             Type classType = classObject.GetType();
@@ -242,22 +333,255 @@ namespace eu.railduction.netcore.dll.Database_Attribute_System
             // Read dbObject-attribute
             DbObject dbObject = ClassAction.Init(classType);
 
+            // Resolve foreignObjects
             foreach (DbForeignObject foreignObjectAtt in dbObject.foreignObjectAttributes)
             {
+                object foreignKey_value = foreignObjectAtt.foreignKeyAttribute.parentField.GetValue(classObject);
                 object foreignObject_value = foreignObjectAtt.parentField.GetValue(classObject);
 
-                // When its empty, get it
+                // When key is set and object is empty, get it & set it
-                if(foreignObject_value == null)
+                if(foreignKey_value != null && foreignObject_value == null)
                 {
-                    foreignObject_value = GetByPrimaryKey<T>(classType, foreignObjectAtt.foreignKeyAttribute.parentField.GetValue(classObject), queryExecutor);
+                    // Resolve it
+                    foreignObject_value = GetByPrimaryKey<T>(foreignObjectAtt.foreignObjectType, foreignKey_value, queryExecutor);
+                    foreignObjectAtt.parentField.SetValue(classObject, foreignObject_value);    // Set the value
+
+                    // Now scan the just resolved class to be able to set myself
+                    DbObject foreignDbObject = Init(foreignObject_value.GetType());
+                    foreach(DbReverseForeignObject dbReverseForeignObject in foreignDbObject.reverseForeignObjectAttributes)
+                    {
+                        // If the field-names match
+                        if(dbReverseForeignObject._foreignKeyName.ToLower() == dbObject.primaryKeyAttributes[0]._attributeName.ToLower())
+                        {
+                            object myReference;
+                            if (dbReverseForeignObject.parentField.FieldType is IList && dbReverseForeignObject.parentField.FieldType.IsGenericType)  // 1:m
+                            {
+                                // If its a list, i create a list with just myself
+                                myReference = new List<T>() { classObject };
+                            }
+                            else    // 1:1
+                            {
+                                // Otherwise ist just myself
+                                myReference = classObject;
+                            }
+                            dbReverseForeignObject.parentField.SetValue(foreignObject_value, myReference);
+                            break;
+                        }
+                    }
                 }
 
                 // Recursive resolving
-                if (max_depth - 1 > 0)
+                if (max_depth > 1)
                 {
+                    // Go recursively into the next class
                     ResolveForeignKeys(foreignObject_value, queryExecutor, max_depth - 1);
                 }
             }
+
+            // Resolve intermediateForeignObjects
+            foreach (DbIntermediateForeignObject intermediateForeignObjectAtt in dbObject.intermediateObjectAttributes)
+            {
+                object intermediateForeignObject_value = intermediateForeignObjectAtt.parentField.GetValue(classObject);
+
+                // When its empty, get it & set it
+                if (intermediateForeignObject_value == null)
+                {
+                    // Generate & set attribute-set
+                    Dictionary<string, object> attributes = new Dictionary<string, object>();
+                    attributes.Add(intermediateForeignObjectAtt._keyName, dbObject.primaryKeyAttributes[0].parentField.GetValue(classObject));
+
+                    string query = QueryBuilder.SelectByAttribute(intermediateForeignObjectAtt._intermediateTableName, attributes);   // Generate query
+                    List<Dictionary<string, object>> dataSet = queryExecutor(query);    // Execute
+                    // Extract data
+                    List<object> values = new List<object>();
+                    for (int i=0; i<dataSet.Count; i++)
+                    {
+                        Dictionary<string, object> data = dataSet[i];
+                        object primaryKeyValue = data[intermediateForeignObjectAtt.foreignPrimaryKeyAttribute._attributeName];
+
+                        values.Add(GetByPrimaryKey<object>(intermediateForeignObjectAtt.foreignPrimaryKeyAttribute.classAttribute.parentClassType, primaryKeyValue, queryExecutor));
+                    }
+
+                    // Now scan the just resolved class to be able to set myself
+                    DbObject foreignDbObject = Init(intermediateForeignObjectAtt.foreignPrimaryKeyAttribute.classAttribute.parentClassType);
+                    foreach (DbForeignObject dbForeignObject in foreignDbObject.foreignObjectAttributes)
+                    {
+                        // If the field-names match
+                        if (dbForeignObject._foreignKeyName.ToLower() == dbObject.primaryKeyAttributes[0]._attributeName.ToLower())
+                        {
+                            object myReference = classObject;
+                            foreach (object value in values)
+                            {
+                                dbForeignObject.parentField.SetValue(value, myReference);
+                            }
+                            break;
+                        }
+                    }
+
+                    // Set value
+                    intermediateForeignObject_value = values;
+                    intermediateForeignObjectAtt.parentField.SetValue(classObject, intermediateForeignObject_value);
+                }
+
+                // Recursive resolving
+                if (max_depth > 1)
+                {
+                    // If we have a list of objects, we need to recursively go into each one
+                    foreach (object value in (IList)intermediateForeignObject_value)
+                    {
+                        ResolveForeignKeys(value, queryExecutor, max_depth - 1);
+                    }
+                }
+            }
+
+            // Resolve reverseForeignObjects
+            foreach (DbReverseForeignObject reverseForeignObjectAtt in dbObject.reverseForeignObjectAttributes)
+            {
+                object reverseForeignObject_value = reverseForeignObjectAtt.parentField.GetValue(classObject);
+                Type reverseForeignObject_type = reverseForeignObjectAtt.parentField.GetType();
+
+                // When its empty, get it & set it
+                if (reverseForeignObject_value == null)
+                {
+                    // Generate & set attribute-set
+                    Dictionary<string, object> attributes = new Dictionary<string, object>();
+                    attributes.Add(reverseForeignObjectAtt._foreignKeyName, dbObject.primaryKeyAttributes[0].parentField.GetValue(classObject));
+
+                    List<object> values = GetListByAttribute<object>(reverseForeignObjectAtt.foreignKeyAttribute.classAttribute.parentClassType, attributes, queryExecutor);
+
+                    if(values.Count == 0) throw new InvalidOperationException($"'{reverseForeignObjectAtt.parentField.Name}' could not been resolved. ReverseForeignObject returned '{values.Count}' values.");
+
+                    // Now scan the just resolved class to be able to set myself
+                    DbObject foreignDbObject = Init(reverseForeignObjectAtt.foreignKeyAttribute.classAttribute.parentClassType);
+                    foreach (DbForeignObject dbForeignObject in foreignDbObject.foreignObjectAttributes)
+                    {
+                        // If the field-names match
+                        if (dbForeignObject._foreignKeyName.ToLower() == dbObject.primaryKeyAttributes[0]._attributeName.ToLower())
+                        {
+                            object myReference = classObject;
+                            foreach(object value in values)
+                            {
+                                dbForeignObject.parentField.SetValue(value, myReference);
+                            }
+                            break;
+                        }
+                    }
+
+                    // Check for type to determen 1:1 or 1:m
+                    if (reverseForeignObject_type is IList && reverseForeignObject_type.IsGenericType)  // List, so 1:m
+                    {
+                        reverseForeignObject_value = values;
+                    }
+                    else    // Not list, so 1:1
+                    {
+                        if (values.Count > 1) throw new InvalidOperationException($"'{reverseForeignObjectAtt.parentField.Name}' could not been resolved as ReverseForeignObject returned '{values.Count}' values. (Is it 1:m instead of 1:1?)");
+                        reverseForeignObject_value = values[0];
+                    }
+                    reverseForeignObjectAtt.parentField.SetValue(classObject, reverseForeignObject_value);
+                }
+
+                // Recursive resolving
+                if (max_depth > 1)
+                {
+                    if (reverseForeignObject_value is IList && reverseForeignObject_type.IsGenericType)  // 1:m
+                    {
+                        // If we have a list of objects, we need to recursively go into each one
+                        foreach(object value in (IList)reverseForeignObject_value)
+                        {
+                            ResolveForeignKeys(value, queryExecutor, max_depth - 1);
+                        }
+                    }
+                    else    // 1:1
+                    {
+                        // Go recursively into the next class
+                        ResolveForeignKeys(reverseForeignObject_value, queryExecutor, max_depth - 1);
+                    } 
+                }
+            }
+        }
+
+
+        /// <summary>
+        /// Updates class to database-object</pragma>
+        /// Only works with primary-key/s!
+        /// </summary>
+        /// <typeparam name="T"></typeparam>
+        /// <param name="classObject">Given object (marked with Db-attributes)</param>
+        /// <param name="queryExecutor">Function to handle query-calls</param>
+        /// <param name="max_depth">Determents how deep resolving will be executed (if the corresponding foreignKey-object is resolved)</param>
+        public static void Update<T>(T classObject, Func<string, List<Dictionary<string, object>>> queryExecutor, int max_depth = 1)
+        {
+            // Read dbObject-attribute
+            DbObject dbObject = ClassAction.Init(classObject.GetType());
+
+            if(max_depth-1 > 0)
+            {
+                // Update all foreignObjects before handling myself
+                foreach (DbForeignObject foreignObject in dbObject.foreignObjectAttributes)
+                {
+                    object foreignObjectRef = foreignObject.parentField.GetValue(classObject);
+                    if (foreignObjectRef != null)
+                        Update(foreignObjectRef, queryExecutor, max_depth - 1);
+                }
+            }
+
+            string updateQuery = QueryBuilder.UpdateByPrimaryKey(classObject);
+            queryExecutor.Invoke(updateQuery);
+        }
+
+        /// <summary>
+        /// Inserts class to database-object
+        /// </summary>
+        /// <typeparam name="T"></typeparam>
+        /// <param name="classObject">Given object (marked with Db-attributes)</param>
+        /// <param name="queryExecutor">Function to handle query-calls</param>
+        /// <param name="max_depth">Determents how deep insertion will be executed (if the corresponding foreignKey-object is resolved)</param>
+        public static void Insert<T>(T classObject, Func<string, List<Dictionary<string, object>>> queryExecutor, int max_depth = 1)
+        {
+            // Read dbObject-attribute
+            DbObject dbObject = ClassAction.Init(classObject.GetType());
+
+            if (max_depth - 1 > 0)
+            {
+                // Update all foreignObjects before handling myself
+                foreach (DbForeignObject foreignObject in dbObject.foreignObjectAttributes)
+                {
+                    object foreignObjectRef = foreignObject.parentField.GetValue(classObject);
+                    if (foreignObjectRef != null)
+                        Insert(foreignObjectRef, queryExecutor, max_depth - 1);
+                }
+            }
+
+            string insertQuery = QueryBuilder.InsertAttributesByObject(classObject);
+            queryExecutor.Invoke(insertQuery);
+        }
+
+        /// <summary>
+        /// Deletes class from database-object</pragma>
+        /// Only works with primary-key/s!
+        /// </summary>
+        /// <typeparam name="T"></typeparam>
+        /// <param name="classObject">Given object (marked with Db-attributes)</param>
+        /// <param name="queryExecutor">Function to handle query-calls</param>
+        /// <param name="max_depth">Determents how deep deletion will be executed (if the corresponding foreignKey-object is resolved)</param>
+        public static void Delete<T>(T classObject, Func<string, List<Dictionary<string, object>>> queryExecutor, int max_depth = 1)
+        {
+            // Read dbObject-attribute
+            DbObject dbObject = ClassAction.Init(classObject.GetType());
+
+            if (max_depth - 1 > 0)
+            {
+                // Update all foreignObjects before handling myself
+                foreach (DbForeignObject foreignObject in dbObject.foreignObjectAttributes)
+                {
+                    object foreignObjectRef = foreignObject.parentField.GetValue(classObject);
+                    if (foreignObjectRef != null)
+                        Delete(foreignObjectRef, queryExecutor, max_depth - 1);
+                }
+            }
+
+            string deleteQuery = QueryBuilder.DeleteByPrimaryKey(classObject);
+            queryExecutor.Invoke(deleteQuery);
         }
     }
 }

Database-Attribute_System/Database-Attribute_System.csproj

@@ -4,7 +4,7 @@
     <TargetFramework>netcoreapp2.1</TargetFramework>
     <RootNamespace>eu.railduction.netcore.dll.Database_Attribute_System</RootNamespace>
     <SignAssembly>false</SignAssembly>
-    <Version>1.5.11</Version>
+    <Version>1.5.3</Version>
   </PropertyGroup>
 
 </Project>

Database-Attribute_System/internal/Function.cs

@@ -14,11 +14,6 @@ namespace eu.railduction.netcore.dll.Database_Attribute_System
             return str_cpy;
         }
 
-        public static string SqlSerialise(DateTime dt, string format = "yyyy-MM-dd HH:mm:ss")
-        {
-            return dt.ToString(format);
-        }
-
         // Recursive object[] copying
         internal static void RecursiveParameterCopying(ref List<object> paramz, object[] objects)
         {
@@ -124,24 +119,24 @@ namespace eu.railduction.netcore.dll.Database_Attribute_System
 
         public static string SqlSerialise(object obj)
         {
-            if (obj == null)            // Handle null
+            if (obj == null || obj is DBNull)            // Handle null
             {
                 return "null";
             }
-            else if (obj.GetType() == typeof(string))       // Handle strings
+            else if (obj is string)       // Handle strings
             {
                 return "'" + SqlEscape((string)obj) + "'";  // wrap in sql-brackets and escape sql, if any
             }
-            else if (obj.GetType() == typeof(byte) || obj.GetType() == typeof(int) || obj.GetType() == typeof(float) || obj.GetType() == typeof(double))  // Handle int, float & double
+            else if (obj is byte || obj is int || obj is float || obj is double)  // Handle int, float & double
             {
                 return obj.ToString().Replace(",", ".");    // just format to string and form comma to sql-comma
             }
-            else if (obj.GetType() == typeof(DateTime))        // Handle DateTime
+            else if (obj is DateTime)        // Handle DateTime
             {
                 DateTime dateTime = (DateTime)obj;
-                return "'" + SqlSerialise(dateTime) + "'";     // wrap in sql-brackets and convert to sql-datetime
+                return "'" + dateTime.ToString("yyyy-MM-dd HH:mm:ss") + "'";     // wrap in sql-brackets and convert to sql-datetime
             }
-            else if (obj.GetType() == typeof(Guid))        // Handle Guid
+            else if (obj is Guid)        // Handle Guid
             {
                 string guid = ((Guid)obj).ToString();  // Get Guid as string
                 return "'" + guid + "'";                 // wrap in sql-brackets