ASP.NET display one message for multiple validators

Question

Let me start by stating what I am really trying to do: I have to check a field for multiple "exclusive" (I'll explain) criteria, and display a single validation message.

Here is my code:

<asp:TextBox ID="Amount" runat="server" CssClass="field"></asp:TextBox>
<asp:RequiredFieldValidator Text="Amount is required"/>
<asp:CompareValidator Operator="DataTypeCheck" Type="Currency" Text="Amount must be numeric"/>
<asp:CompareValidator Operator="GreaterThanEqual" ValueToCompare="10" Type="Currency" Text="Minimum donation $10.00"/>
<asp:CompareValidator Operator="LessThan" ValueToCompare="10000" Type="Currency" Text="Wow that's too much"/>

I have left off some tags for readability - all validators are in the same validation group, they have ID's, ControlToValidate="Amount" Display="Dynamic".

If the Amount field is blank, or has a number in it, all is fine. However, if I put text in the field:

Even though the <10, >10,000 and DataTypeCheck should be exclusive, the numeric comparisons fail on the string.

I realize I could use a CustomValidator for this, but I would like to eventually style one the messages differently, in its own separate <span> element.

So, my incorrect (because they aren't "What am I really trying to do?") questions are:

1. How do I make a CompareValidator of currency type not fail on text? or
2. How do I display only the first message from multiple validators? or
3. How do I do what I want to do?

Answer 1

$(document).ready(function() {
$("#txtboxToFilter").keydown(function(event) {
    // Allow only backspace and delete
    if ( event.keyCode == 46 || event.keyCode == 8 ) {
        // let it happen, don't do anything
    }
    else {
        // Ensure that it is a number and stop the keypress
        if (event.keyCode > 48 || event.keyCode < 57 ) {
            event.preventDefault(); 
        }   
    }
});

});

Also, if you are using HTML5 you could simply use

EDIT 1 corrected the comparison operator to allow digits 0-9.

Answer 2

So I ended up using a CustomValidator and setting a label where I wanted my different message.

.aspx page:

<span>
    <asp:TextBox ID="Amount" runat="server" CssClass="field"></asp:TextBox>
    <asp:RequiredFieldValidator [same as earlier...] />
    <asp:CustomValidator ID="AmountCustomValidator" ControlToValidate="Amount" ValidateEmptyText="False" OnServerValidate="AmountCustomValidator_ServerValidate"/>
</span>
<span>
    <asp:Label ID="AmountTooMuchMessage" runat="server" Text="" />
</span>

Code-behind:

protected void AmountCustomValidator_ServerValidate(object source, ServerValidateEventArgs args)
{
    args.IsValid = true;
    AmountTooMuchMessage.Text = ""; //Reset special error label text

    decimal amountFormatted;

    if (!decimal.TryParse(args.Value, out amountFormatted))
    {
        AmountCustomValidator.Text = "Amount must be numeric";
        args.IsValid = false;
        return; //Don't try to compare values to non-numeric input
    }

    //This is money, so make it two decimals
    amountFormatted = Math.Round(amountFormatted, 2);
    Amount.Text = amountFormatted.ToString();

    if (amountFormatted < 10)
    {
        AmountCustomValidator.Text = "Minimum donation $10.00";
        args.IsValid = false;
    }

    if (amountFormatted > 10000)
    {
        AmountCustomValidator.Text = "";
        AmountTooMuchMessage.Text = "That's too much";
        args.IsValid = false;
    }
}

Note that I had to remove the ErrorMessage tag on the CustomValidator, otherwise it will show when Text="".