Why wouldn't this work ?  Anybody know ?  The error I get is JavaScript runtime error: Unable to get property 'value' of undefined or null reference
When debug the function it says ->   tel Undefined

function ValidatePhone(tel) { var error = ""; var stripped = tel.value.replace(/[\.\@\!\#\$\%\^\&\*\=\_\|\ ]/g, ''); if (tel.value == "") { error = "You didn't enter a phone number.\n"; } else if (isNaN(parseInt(stripped))) { error = "The phone number contains illegal characters.\n"; } else if (!(stripped.length == 10)) { error = "The phone number is the wrong length. Make sure you included an area code.\n"; } return error; } <asp:TextBox ID="txtphone" runat="server" Width="100 ...

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