CompareValidator asp.net Type:String - asp.net

Question

I am trying to use CompareValidator witch compare the field for string.and the
server code to write in the Label1 the result.I tried with integer and date data types and it
work fine but when i put string its not working.When i put integer in the field it consider that is true.How to make it work.
<asp:TextBox ID="name" runat="server" CausesValidation="True" MaxLength="40"> </asp:TextBox>
<asp:CompareValidator
ID="CompareValidator1"
runat="server"
ControlToValidate="name"
Operator="DataTypeCheck"
Type="String">
</asp:CompareValidator>
<asp:Label ID="Label1" runat="server" Text="Label" Visible="True"></asp:Label>
<asp:Button ID="Button1" runat="server" Text="Изпрати" BackColor="Black" BorderColor="Black" BorderStyle="None" ForeColor="White" OnClick="PageValidate_SendMail" />
protected void PageValidate_SendMail(object sender, EventArgs e)
{
if (Page.IsValid) {
Label1.Text = "String";
}
else {
Label1.Text = "Integer";
}
}

Answer 1

What you will need is RegularExpressionValidator something like below. The ValidationExpression="^[a-zA-Z]*$ restricts input to alphabets only.
<asp:RegularExpressionValidator ID="RegularExpressionValidator1" runat="server" ControlToValidate="name" ValidationExpression="^[a-zA-Z]*$" ErrorMessage="RegularExpressionValidator" Display="Dynamic"></asp:RegularExpressionValidator>
You might want to use RequiredFieldValidator as well for checking empty input.
And if none of those meet your requirements then you will need to use CustomValidator.