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Color Dialog
A ColorDialog in C# is like a pop-up window that shows a bunch of colors
to choose from. You can use it in your program to let users pick a color
easily. When they select a color and close the window, your program gets to
know which color they chose. To open this color window, you just need to call
the `ShowDialog()` method.
In C#, the ColorDialog control lets users pick a color from a range of
pre-defined colors, as well as create their own custom colors. When you use a
Color Dialog, it usually displays a list of common solid colors for easy
selection. Additionally, it provides an option for users to define their own
custom colors. This allows users to pick from a wider spectrum beyond just the
predefined colors.
ColorDialog dlg = new ColorDialog();
dlg.ShowDialog();
Example for return selected color name:
ColorDialog dlg = new ColorDialog();
dlg.ShowDialog();
if (dlg.ShowDialog() == DialogResult.OK)
{
string str = null;
str =
dlg.Color.Name;
MessageBox.Show
(str);
}
Creating a ColorDialog
Creating a ColorDialog control in C# can be done either using a Forms
designer during design-time or programmatically using the ColorDialog class at
run-time. Unlike other Windows Forms controls, a ColorDialog doesn't have
visual properties as its main purpose is to display available colors, allow
users to create custom colors, and select a color from them. Once a color is
selected, it can be captured and used in the code to apply it to other
controls. While it's possible to create a ColorDialog at design-time, it's
often simpler and more flexible to create it at run-time programmatically.
Design-time
To create a ColorDialog control at design-time in Visual Studio, you can
easily do so by dragging and dropping a ColorDialog control from the Toolbox
onto a Form. Once added, the ColorDialog appears on the Form and can be
configured as needed.
Run-time
To create a ColorDialog control dynamically at run-time, you start by
creating an instance of the ColorDialog class. The following code snippet
demonstrates how to create a ColorDialog object:
ColorDialog colorDialog = new ColorDialog();
This line of code instantiates a new ColorDialog object named
`colorDialog`, which can then be further configured and added to the Form's
controls as needed.
ShowDialog method of ColorDialog displays the ColorDialog. The following
code snippet sets background color, foreground color, Text, Name, and Font
properties of a ColorDialog.
colorDlg.ShowDialog();
ColorDialog Properties
After placing a ColorDialog control on a Form, the next step is to
configure its properties. The easiest way to do this is through the Properties
Window. You can open the Properties window by pressing F4 or by right-clicking
on the control and selecting the Properties menu item. The Properties window
provides a convenient interface for modifying various properties of the
ColorDialog control.
AllowFullOpen
In Figure 1, there's a button labeled "Define Custom Colors"
on the ColorDialog. Clicking on this button opens the custom color editor area.
Here, users can define colors by setting RGB color values ranging from 0 to
255. Additionally, users can select a color from the color area, as shown in
Figure 4. This feature allows users to create custom colors beyond the
predefined ones.
Setting the AllowFullOpen property to false on a ColorDialog disables
the "Define Custom Color" option, ensuring it is not available. As a
result, the ColorDialog will resemble Figure 5, where the custom color option
is not visible or accessible to users.
Example
private void button1_Click(object sender, EventArgs e)
{
//colorDialog1.ShowDialog();
if
(colorDialog1.ShowDialog() == DialogResult.OK)
{
this.BackColor =
colorDialog1.Color;
}
}
private void button2_Click(object sender, EventArgs e)
{
MessageBox.Show(colorDialog1.Color.Name);
}