i have one textbox iam using this textbox only in text so i want to put one validate control when ever enter some numbers that time the validator automatically show error message.

if ((e.KeyChar >= 65 && e.KeyChar <= 90) || (e.KeyChar >= 97 && e.KeyChar <= 122) || e.KeyChar == 32 || e.KeyChar == 8)
            {
                e.Handled = false;
            }
            else
            {
                MessageBox.Show("Only Character");
                e.Handled = true;
            }

public bool IsAlpha(string input)
{
    return Regex.IsMatch(input, "^[a-zA-Z]+$");
}
public bool IsAlphaNumeric(string input)
{
    return Regex.IsMatch(input, "^[a-zA-Z0-9]+$");
}

public bool IsAlphaNumericWithUnderscore(string input)
{
    return Regex.IsMatch(input, "^[a-zA-Z0-9_]+$");
}

script type="text/javascript" language="javascript">
    function validateNumbersOnly(e) {
        var unicode = e.charCode ? e.charCode : e.keyCode;
        if ((unicode == 8) || (unicode == 9) || (unicode > 47 && unicode < 58)) {
            return true;
        }
        else {

            window.alert("This field accepts only Numbers");
            return false;
        }
    }
</script>

<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
<asp:RegularExpressionValidator ID="RegularExpressionValidator6" runat="server" Display="None" ErrorMessage="Accepts only numbers." ControlToValidate="TextBox1" ValidationExpression=""^[0-9]*$" Text="*"></asp:RegularExpressionValidator>