本文整理匯總了C#中System.Windows.Forms.KeyEventHandler代理的典型用法代碼示例。如果您正苦於以下問題：C# KeyEventHandler代理的具體用法？C# KeyEventHandler怎麽用？C# KeyEventHandler使用的例子？那麽, 這裏精選的代理代碼示例或許可以為您提供幫助。
KeyEventHandler代理屬於System.Windows.Forms命名空間，在下文中一共展示了KeyEventHandler代理的2個代碼示例，這些例子默認根據受歡迎程度排序。您可以為喜歡或者感覺有用的代碼點讚，您的評價將有助於係統推薦出更棒的C#代碼示例。
示例1: treeView1_KeyDown
private void treeView1_KeyDown(object sender, KeyEventArgs e)
{
/* If the 'Alt' and 'E' keys are pressed,
* allow the user to edit the TreeNode label. */
if(e.Alt && e.KeyCode == Keys.E)
{
treeView1.LabelEdit = true;
// If there is a TreeNode under the mouse cursor, begin editing.
TreeNode editNode = treeView1.GetNodeAt(
treeView1.PointToClient(System.Windows.Forms.Control.MousePosition));
if(editNode != null)
{
editNode.BeginEdit();
}
}
}
private void treeView1_AfterLabelEdit(object sender, NodeLabelEditEventArgs e)
{
// Disable the ability to edit the TreeNode labels.
treeView1.LabelEdit = false;
}示例2: textBox1_KeyDown
// Boolean flag used to determine when a character other than a number is entered.
private bool nonNumberEntered = false;
// Handle the KeyDown event to determine the type of character entered into the control.
private void textBox1_KeyDown(object sender, System.Windows.Forms.KeyEventArgs e)
{
// Initialize the flag to false.
nonNumberEntered = false;
// Determine whether the keystroke is a number from the top of the keyboard.
if (e.KeyCode < Keys.D0 || e.KeyCode > Keys.D9)
{
// Determine whether the keystroke is a number from the keypad.
if (e.KeyCode < Keys.NumPad0 || e.KeyCode > Keys.NumPad9)
{
// Determine whether the keystroke is a backspace.
if(e.KeyCode != Keys.Back)
{
// A non-numerical keystroke was pressed.
// Set the flag to true and evaluate in KeyPress event.
nonNumberEntered = true;
}
}
}
//If shift key was pressed, it's not a number.
if (Control.ModifierKeys == Keys.Shift) {
nonNumberEntered = true;
}
}
// This event occurs after the KeyDown event and can be used to prevent
// characters from entering the control.
private void textBox1_KeyPress(object sender, System.Windows.Forms.KeyPressEventArgs e)
{
// Check for the flag being set in the KeyDown event.
if (nonNumberEntered == true)
{
// Stop the character from being entered into the control since it is non-numerical.
e.Handled = true;
}
}