方法一：
private void tBox_KeyPress(object sender, KeyPressEventArgs e)
{
if (e.KeyChar == 0x20) e.KeyChar = (char); //禁止空格键
if ((e.KeyChar == 0x2D) && (((TextBox)sender).Text.Length == )) return; //处理负数
if (e.KeyChar > 0x20)
{
try
{
double.Parse(((TextBox)sender).Text + e.KeyChar.ToString());
}
catch
{
e.KeyChar = (char); //处理非法字符
}
}
}
方法二：
private void TextBox_KeyPress(object sender, KeyPressEventArgs e)
{
if(e.KeyChar!=&&!Char.IsDigit(e.KeyChar))
{
e.Handled = true;
}
}
或者
private void TextBox_KeyPress(object sender, KeyPressEventArgs e)
{
if(e.KeyChar!='\b'&&!Char.IsDigit(e.KeyChar))
{
e.Handled = true;
}
}
方法三:
private void textBox1_KeyPress(object sender, System.Windows.Forms.KeyPressEventArgs e)
{
if(e.KeyChar!='\b')//这是允许输入退格键
{
if((e.KeyChar<'')||(e.KeyChar>''))//这是允许输入0-9数字
{
e.Handled = true;
}
}
}
方法四:
private void textBox1_Validating(object sender, CancelEventArgs e)
{
const string pattern = @"^\d+\.?\d+{1}quot;;
string content = ((TextBox)sender).Text;
if (!(Regex.IsMatch(content, pattern)))
{
errorProvider1.SetError((Control)sender, "只能输入数字!");
e.Cancel = true;
}
else
errorProvider1.SetError((Control)sender, null);
}
方法五:
private void textBox1_KeyPress(object sender, System.Windows.Forms.KeyPressEventArgs e)
{
if(e.KeyChar=='.' && this.textBox1.Text.IndexOf(".")!=-)
{
e.Handled=true;
}
if(!((e.KeyChar>= && e.KeyChar<=) || e.KeyChar=='.' || e.KeyChar==))
{
e.Handled=true;
}
}
方法六：
private void tbx_LsRegCapital_KeyPress(object sender, KeyPressEventArgs e)
{
if (!Char.IsNumber(e.KeyChar) && !Char.IsPunctuation(e.KeyChar) && !Char.IsControl(e.KeyChar))
{
e.Handled = true;//消除不合适字符
}
else if (Char.IsPunctuation(e.KeyChar))
{
if (e.KeyChar != '.' || this.textBox1.Text.Length == )//小数点
{
e.Handled = true;
}
if (textBox1.Text.LastIndexOf('.') != -)
{
e.Handled = true;
}
}
}
方法七:
利用ASCII码处理办法、
{
if ((e.KeyChar <= || e.KeyChar >=) && (e.KeyChar != ) && (e.KeyChar != ))
e.Handled = true;
================48代表0，57代表9，8代表空格，46代表小数点
}