C#文本框限制按键输入
对照ASCII码表
1.仅支持输入数字
private void txt_KeyPress(object sender, KeyPressEventArgs e)
{
if (e.KeyChar != 8 && !Char.IsDigit(e.KeyChar))
{
e.Handled = true; //禁止输入
}
}
2.仅支持输入数字和字母
private void txt_KeyPress(object sender, KeyPressEventArgs e)
{
if (e.KeyChar != 8 &&!Char.IsLetterOrDigit(e.KeyChar))
{
e.Handled = true;
}
}
3.输入年龄 《120岁
private void txtAge_KeyPress(object sender, KeyPressEventArgs e)
{
if (Char.IsDigit(e.KeyChar))
{
e.Handled = (Convert.ToInt16(this.txtAge.Text + e.KeyChar) >120);
}
else if(e.KeyChar == 8)
{
e.Handled = false;
}
else
{
e.Handled = true;
}
}
4.判断是否是邮箱格式
public bool IsEmail(string value)
{
return System.Text.RegularExpressions.Regex.IsMatch(value, @"\w+([-+.]\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*");
}
