本文整理汇总了C#中System.Windows.Forms.KeyPressEventHandler代理的典型用法代码示例。如果您正苦于以下问题：C# KeyPressEventHandler代理的具体用法？C# KeyPressEventHandler怎么用？C# KeyPressEventHandler使用的例子？那么恭喜您, 这里精选的代理代码示例或许可以为您提供帮助。
KeyPressEventHandler代理属于System.Windows.Forms命名空间，在下文中一共展示了KeyPressEventHandler代理的2个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的C#代码示例。
示例1: Form1
//引入命名空间
using System;
using System.Windows.Forms;
public class Form1: Form
{
public Form1()
{
// Create a TextBox control.
TextBox tb = new TextBox();
this.Controls.Add(tb);
tb.KeyPress += new KeyPressEventHandler(keypressed);
}
private void keypressed(Object o, KeyPressEventArgs e)
{
// The keypressed method uses the KeyChar property to check
// whether the ENTER key is pressed.
// If the ENTER key is pressed, the Handled property is set to true,
// to indicate the event is handled.
if (e.KeyChar == (char)Keys.Return)
{
e.Handled = true;
}
}
public static void Main()
{
Application.Run(new Form1());
}
}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;
}
}