I suggest you set these ColorDialog Properties:
AnyColor = true;
FullOpen = true;
Then, when you use the ColorDialog like this:
private void btnOpenColorDialog_Click(object sender, EventArgs e)
{
colorDialog1.Color = textBox1.BackColor;
colorDialog1.ShowDialog();
textBox1.BackColor = colorDialog1.Color;
}
If the current BackColor of the TextBox is not one of the
standard 48 solid colors, at least the color-picker displayed on the right will show you the current TextBox BackColor.
To make custom colors you define
persist in the 16-slots provided for custom color definitions you need to do several things:
0. select a slot from the 16 slots for custom colors.
1. move the cross-hairs to select a color
2. set the color intensity using the vertical slider on the far right
3. click somewhere
in that vertical slider
4. click the "Add to custom colors" button
5. click okay