Implemented the MySqlColumn converter and added more example code. Improved documentation. Added new DeleteAll function.

MySqlPlus.Example/Program.cs

@@ -20,18 +20,51 @@ namespace MontoyaTech.MySqlPlus.Example
             [MySqlColumn("year")]
             public uint Year = 0;
 
-            //[MySqlColumn("dateCreated", typeof(DateTime2UnixConverter))]
+            [MySqlColumn("dateCreated", typeof(DateTime2UnixConverter))]
-            //public DateTime DateCreated = DateTime.UtcNow;
+            public DateTime DateCreated = DateTime.UtcNow;
         }
 
-        public class DateTime2UnixConverter
+        public class DateTime2UnixConverter : MySqlColumnConverter
         {
+            public object ConvertFrom(object input)
+            {
+                if (input is ulong unix)
+                {
+                    if (unix == 0)
+                        return DateTime.MinValue;
 
+                    return new DateTime(1970, 1, 1, 0, 0, 0, 0, DateTimeKind.Utc).AddSeconds(unix).ToUniversalTime();
+                }
+                else
+                {
+                    throw new NotSupportedException("Unsupported input object to convert from unix.");
+                }
+            }
+
+            public object ConvertTo(object input)
+            {
+                if (input is DateTime dateTime)
+                {
+                    if (dateTime == DateTime.MinValue)
+                        return 0;
+
+                    if (dateTime == DateTime.MaxValue)
+                        return ulong.MaxValue;
+
+                    return (ulong)(dateTime.ToUniversalTime().Subtract(new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc))).TotalSeconds;
+                }
+                else
+                {
+                    throw new NotSupportedException("Unsupported input object to convert to unix.");
+                }
+            }
         }
 
         public static void Main(string[] args)
         {
-            var session = new MySqlSession("server=db.zone2d.com;user=root;database=zone2d;port=3306;password=-+W6!?Kv-6wDL2Vj5f=kC^Q&;SslMode=Required");
+            var session = new MySqlSession("");
+
+            session.DeleteAll<Car>();
 
             session.Insert(new Car() { Make = "Chevy", Model = "Camaro", Year = 2011 });
 
@@ -40,7 +73,7 @@ namespace MontoyaTech.MySqlPlus.Example
             var cars = session.GetAll<Car>();
 
             foreach (var car in cars)
-                Console.WriteLine($"Make: {car.Make}, Model: {car.Model}, Year: {car.Year}");
+                Console.WriteLine($"Make: {car.Make}, Model: {car.Model}, Year: {car.Year}, DateCreated: {car.DateCreated}");
 
             cars[0].Make = "test";
 

MySqlPlus/MySqlColumn.cs

@@ -16,21 +16,52 @@ namespace MontoyaTech.MySqlPlus
     [AttributeUsage(AttributeTargets.Field, AllowMultiple = false, Inherited = true)]
     public class MySqlColumn : Attribute
     {
+        /// <summary>
+        /// Whether or not this column is the row id.
+        /// </summary>
         public bool Id = false;
 
+        /// <summary>
+        /// The name of the column, if null, the field name will be used instead.
+        /// </summary>
         public string Name = null;
 
+        /// <summary>
+        /// An optional MySqlColumnConverter that can convert this column to another
+        /// data type when needed.
+        /// </summary>
         public Type Converter = null;
 
+        /// <summary>
+        /// Creates a new default MySqlColumn.
+        /// </summary>
         public MySqlColumn() { }
 
+        /// <summary>
+        /// Creates a new MySqlColumn with a name and column converter if needed.
+        /// </summary>
+        /// <param name="name"></param>
+        /// <param name="converter"></param>
+        /// <exception cref="NotSupportedException"></exception>
         public MySqlColumn(string name, Type converter = null)
         {
             this.Name = name;
 
+            //Make sure the converter is valid if one was passed.
+            if (converter != null && !converter.IsAssignableTo(typeof(MySqlColumnConverter)))
+                throw new NotSupportedException($"Converter must inherit {nameof(MySqlColumnConverter)}");
+
             this.Converter = converter;
         }
 
+        /// <summary>
+        /// Reads this column from a given data reader and stores the value into the provided field on a row.
+        /// </summary>
+        /// <typeparam name="T"></typeparam>
+        /// <param name="row"></param>
+        /// <param name="field"></param>
+        /// <param name="reader"></param>
+        /// <exception cref="NotSupportedException"></exception>
         public void ReadValue<T>(T row, FieldInfo field, MySqlDataReader reader)
         {
             //See if we can find the column index.
@@ -51,6 +82,13 @@ namespace MontoyaTech.MySqlPlus
             if (columnIndex == -1)
                 return;
 
+            //See if we have a converter, use it to read the value.
+            if (this.Converter != null)
+            {
+                field.SetValue(row, this.Converter.CreateInstance<MySqlColumnConverter>().ConvertFrom(reader.GetValue(columnIndex)));
+            }
+            else
+            {
                 //Get our field type code
                 var typeCode = Type.GetTypeCode(field.FieldType);
 
@@ -107,4 +145,5 @@ namespace MontoyaTech.MySqlPlus
                 }
             }
         }
+    }
 }

MySqlPlus/MySqlColumnConverter.cs

@@ -0,0 +1,29 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace MontoyaTech.MySqlPlus
+{
+    /// <summary>
+    /// The outline of a MySqlColumnConverter that can convert a
+    /// columns value from one type to another and back.
+    /// </summary>
+    public interface MySqlColumnConverter
+    {
+        /// <summary>
+        /// Converts the input value to the desired type the database expects.
+        /// </summary>
+        /// <param name="input"></param>
+        /// <returns></returns>
+        object ConvertTo(object input);
+
+        /// <summary>
+        /// Converts the input value from a database type to the desired type.
+        /// </summary>
+        /// <param name="input"></param>
+        /// <returns></returns>
+        object ConvertFrom(object input);
+    }
+}

MySqlPlus/MySqlCommandExtensions.cs

@@ -60,7 +60,7 @@ namespace MontoyaTech.MySqlPlus
 
                 builder.Append($"`{(string.IsNullOrWhiteSpace(column.Name) ? fields[i].Name : column.Name)}` = @{i}");
 
-                command.Parameters.AddWithValue($"@{i}", fields[i].GetValue(row));
+                command.Parameters.AddWithValue($"@{i}", (column.Converter == null ? fields[i].GetValue(row) : column.Converter.CreateInstance<MySqlColumnConverter>().ConvertTo(fields[i].GetValue(row))));
 
                 seperate = true;
             }
@@ -122,7 +122,7 @@ namespace MontoyaTech.MySqlPlus
 
                 builder.Append($"`{(string.IsNullOrWhiteSpace(column.Name) ? fields[i].Name : column.Name)}` = @{i}");
 
-                command.Parameters.AddWithValue($"@{i}", fields[i].GetValue(row));
+                command.Parameters.AddWithValue($"@{i}", (column.Converter == null ? fields[i].GetValue(row) : column.Converter.CreateInstance<MySqlColumnConverter>().ConvertTo(fields[i].GetValue(row))));
 
                 seperate = true;
             }
@@ -257,5 +257,28 @@ namespace MontoyaTech.MySqlPlus
             //Set the command text.
             command.CommandText = builder.ToString();
         }
+
+        /// <summary>
+        /// Setups this MySqlCommand to delete all rows of a given type from the db.
+        /// </summary>
+        /// <typeparam name="T"></typeparam>
+        /// <param name="command"></param>
+        public static void DeleteAll<T>(this MySqlCommand command)
+        {
+            //Get the type of T
+            var type = typeof(T);
+
+            //Get the row information.
+            var rowAttribute = type.GetCustomAttribute<MySqlRow>();
+
+            //Start building the query.
+            var builder = new StringBuilder();
+
+            //Write the delete from section
+            builder.Append($"DELETE FROM `{(rowAttribute == null || string.IsNullOrWhiteSpace(rowAttribute.Name) ? type.Name : rowAttribute.Name)}`");
+
+            //Set the command text.
+            command.CommandText = builder.ToString();
+        }
     }
 }

MySqlPlus/MySqlPlus.csproj

@@ -1,4 +1,4 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
     <TargetFramework>net6.0</TargetFramework>

MySqlPlus/MySqlSession.cs

@@ -174,6 +174,21 @@ namespace MontoyaTech.MySqlPlus
             }
         }
 
+        /// <summary>
+        /// Deletes all the rows of a given type in the db.
+        /// </summary>
+        /// <typeparam name="T">The type of row to delete.</typeparam>
+        /// <returns>The number of rows affected</returns>
+        public int DeleteAll<T>()
+        {
+            using (var command = new MySqlCommand())
+            {
+                command.DeleteAll<T>();
+
+                return this.Connection.ExecuteNonQuery(command);
+            }
+        }
+
         /// <summary>
         /// Implicitly converts a MySqlSession to a MySqlConnection.
         /// </summary>