You can use the BorderColorChanged event when the value of the BorderColor property changes.

To create a message box when the border color changes for C1TextBox, complete the following:

1. Add a C1TextBox control to your form.
2. Navigate to C1TextBox’s properties window and change the BorderStyle property to "FixedSingle".
3. Add a MouseClick event to the C1TextBox control to change C1TextBox’s border color to purple.

   To write code in Visual Basic

   Visual Basic	Copy Code
   Private Sub C1TextBox1_MouseClick(ByVal sender As System.Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles C1TextBox1.MouseClick C1TextBox1.BorderColor = Color.Purple End Sub

   To write code in C#

   C#	Copy Code
   private void c1TextBox1_MouseClick(object sender, MouseEventArgs e) { c1TextBox1.BorderColor = Color.Purple; }

4. Add a BorderColorChanged event to C1TextBox1 to show a message box that informs the user the border color has changed.

   To write code in Visual Basic

   Visual Basic	Copy Code
   Private Sub C1TextBox1_BorderColorChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles C1TextBox1.BorderColorChanged MessageBox.Show(“The C1TextBox1 border color change to purple”) End Sub

   To write code in C#

   C#	Copy Code
   private void c1TextBox1_BorderColorChanged(object sender, EventArgs e) { MessageBox.Show("The c1TextBox1 border color changed to purple"); }

When you mouse click on the C1TextBox control the border color changes to purple. Once it changes to purple the BorderColorChanged event fires and a message box appears informing the user that the border color has changed.