Event Handling in Windows Forms Double TextBox

4 Feb 20252 minutes to read

DoubleValueChanged Event

This DoubleValueChanged event is handled when the double value in the text field is changed.

C#

private void doubleTextBox1_DoubleValueChanged(object sender, EventArgs e)
{
   MessageBox.Show("Double Value is changed");
}

VB.NET

Private Sub doubleTextBox1_DoubleValueChanged(ByVal sender As Object, ByVal e As EventArgs)
MessageBox.Show("Double Value is changed")
End Sub

Enabling Fixed Change using Shortcut Keys

Sometimes there may occur situations for incrementing or decrementing the value in DoubleTextBox. In such situations it is better to use shortcut keys. The following implementation will give you an idea on how to achieve this. Here the Up and Down keys are used for incrementing and decrementing respectively. We cannot use ‘-‘ because it is already reserved to enter the minus sign.

C#

private void doubleTextBox1_KeyDown(object sender,KeyEventArgs e)
{
    decimal v=doubleTextBox1.DoubleValue;
    switch(e.KeyCode)
    {
        // Up and Down keys are used for incrementing and decrementing respectively.
        case Keys.Up : v++;break;
        case Keys.Down : v--;break;
    }
    doubleTextBox1.DoubleValue=v;
}

VB.NET

Private Sub doubleTextBox1_KeyDown(ByVal sender As Object, ByVal e As KeyEventArgs)
Dim v As Decimal = doubleTextBox1.DoubleValue
Select e.KeyCode
' Up and Down keys are used for incrementing and decrementing respectively.
Case Keys.Up
v=v+1
Case Keys.Down
v=v-1
End Select
doubleTextBox1.DoubleValue = v
End Sub