Color Properties in Entity Framework

• Mar 12, 2021
• 2 minutes to read

The following example demonstrates how to store a System.Drawing.Color property value in the database managed by the Entity Framework ORM. The approach is based on converting the System.Drawing.Color type to the System.Int32 using an auxiliary hidden integer property.

C#

using System.ComponentModel.DataAnnotations.Schema;
using System.Drawing;
//...
[Browsable(false), Column("Color")]
public int Argb {
    get { return fColor.ToArgb(); }
    set { fColor = Color.FromArgb(value); }
}
private Color fColor;
[NotMapped]
public Color Color {
    get { return fColor; }
    set { fColor = value; }
}

VB.NET

Imports System.ComponentModel.DataAnnotations.Schema
Imports System.Drawing
'...
<Browsable(False), Column("Color")> _
Public Property Argb() As Integer
    Get
        Return fColor.ToArgb()
    End Get
    Set(ByVal value As Integer)
        fColor = Color.FromArgb(value)
    End Set
End Property
Private fColor As Color
<NotMapped> _
Public Property Color() As Color
    Get
        Return fColor
    End Get
    Set(ByVal value As Color)
        fColor = value
    End Set
End Property

If the type does not have an appropriate conversion method (Color.ToArgb in this example), implement a Type Converter and use it any time you need to covert a value from the type you need to store to an ORM-friendly type.

Note

Object Space is not marked modified when the non-persistent Color property is changed. If this behavior does not fit your requirements, set the BaseObjectSpace.NonPersistentChangesEnabled property to true.