winform textbox 控件只允许输入数字，不能以0开头数字

private void txt_n_KeyPress(object sender, KeyPressEventArgs e)
        {
            if (e.KeyChar != '\b')   //允许输入退格键  
            {
                int len = txt_jine.Text.Length;
                if (len < 1 && e.KeyChar == '0')
                {
                    e.Handled = true ;
                }
                else if ((e.KeyChar < '0') || (e.KeyChar > '9'))//这是允许输入0-9数字  
                {
                    e.Handled = true;
                }

            }
        }

转载于:https://my.oschina.net/xiaoxiezi/blog/3079225