A C# ColorDialog control is used to select a color from available colors and also define custom colors. A typical Color Dialog looks like Figure 1 where you can see there is a list of basic solid colors and there is an option to create custom colors.

ColorDialogImg1.jpg
Figure 1

Creating a ColorDialog

We can create a ColorDialog control using a Forms designer at design-time or using the ColorDialog class in code at run-time (also known as dynamically). Unlike other Windows Forms controls, a ColorDialog does not have and not need visual properties like others. The only purpose of ColorDialog to display available colors, create custom colors and select a color from these colors. Once a color is selected, we need that color in our code so we can apply it on other controls.

Again, you can create a ColorDialog at design-time but It is easier to create a ColorDialog at run-time.

Design-time

To create a ColorDialog control at design-time, you simply drag and drop a ColorDialog control from Toolbox to a Form in Visual Studio. After you drag and drop a ColorDialog on a Form, the ColorDialog looks like Figure 2.

ColorDialogImg2.jpg
Figure 2

Adding a ColorDialog to a Form adds following two lines of code.

  1. private System.Windows.Forms.ColorDialog colorDialog1;
  2. this.colorDialog1 = new System.Windows.Forms.ColorDialog();
Run-time
Creating a ColorDialog control at run-time is merely a work of creating an instance of ColorDialog class, set its properties and add ColorDialog class to the Form controls.
First step to create a dynamic ColorDialog is to create an instance of ColorDialog class. The following code snippet creates a ColorDialog control object.

  1. ColorDialog colorDlg = new ColorDialog();

ShowDialog method of ColorDialog displays the ColorDialog. The following code snippet sets background color, foreground color, Text, Name, and Font properties of a ColorDialog.

  1. colorDlg.ShowDialog();
Once the ShowDialog method is called, you can pick colors on the dialog.

ColorDialog Properties

After you place a ColorDialog control on a Form, the next step is to set properties.

The easiest way to set properties is from the Properties Window. You can open Properties window by pressing F4 or right click on a control and select Properties menu item. The Properties window looks like Figure 3.

ColorDialogImg3.jpg
Figure 3

AllowFullOpen

If you look at Figure 1, you will see a button called Define Custom Colors on the ColorDialog. Clicking on this button opens the custom color editor area where you can define colors by setting RGB color values (between 0 to 255) and can also select a color from the color area as you can see in Figure 4.

ColorDialogImg4.jpg
Figure 4

AllowFullOpen property makes sure that Define Custom Color option is enabled on a ColorDialog. If you wish to disable this option, you can set AllowFullOpen property to false and your ColorDialog will look like Figure 5.

ColorDialogImg5.jpg
Figure 5

The following code snippet sets the AllowFullOpen property to false.
  1. colorDlg.AllowFullOpen = false;

Color, AnyColor, and SolidColorOnly

Color property is used to get and set the color selected by the user in a ColorDialog.
AnyColor is used to get and set whether a ColorDialog displays all available colors in the set of basic colors.
SolidColorOnly is used to get and set whether a ColorDialog restricts users to selecting solid colors only.
The following code snippet sets these properties.
  1. colorDlg.AnyColor = true;
  2. colorDlg.SolidColorOnly = false;
  3. colorDlg.Color = Color.Red;

ColorDialog Code Example

Now let's create an application that will use a ColorDialog to set colors of bunch of controls. The Windows Forms application looks like Figure 6.

ColorDialogImg6.jpg
Figure 6

In Figure 6, we have a few Windows Forms controls and clicking on Foreground Color and Background Color buttons will let user select a color and set that color as foreground and background colors of the controls. After selecting foreground and background colors, the Form looks like Figure 7.

ColorDialogImg7.jpg
Figure 7

The following code snippet is the code for Foreground Color and Background Color buttons click event handlers.
  1. private void ForegroundButton_Click(object sender, EventArgs e)
  2. {
  3. ColorDialog colorDlg = new ColorDialog();
  4. colorDlg.AllowFullOpen = false;
  5. colorDlg.AnyColor = true;
  6. colorDlg.SolidColorOnly = false;
  7. colorDlg.Color = Color.Red;
  9. if (colorDlg.ShowDialog() == DialogResult.OK)
  10. {
  11. textBox1.ForeColor = colorDlg.Color;
  12. listBox1.ForeColor = colorDlg.Color;
  13. button3.ForeColor = colorDlg.Color;
  14. }
  15. }
  18. private void BackgroundButton_Click(object sender, EventArgs e)
  19. {
  20. ColorDialog colorDlg = new ColorDialog();
  21. if (colorDlg.ShowDialog() == DialogResult.OK)
  22. {
  23. textBox1.BackColor = colorDlg.Color;
  24. listBox1.BackColor = colorDlg.Color;
  25. button3.BackColor = colorDlg.Color;
  26. }
  27. }

Summary

A ColorDialog control allows users to launch Windows Color Dialog and let them select a solid color or create a custom color from available colors. In this article, we discussed how to use a Windows Color Dialog and set its properties in a Windows Forms application.