How do I pass a custom attribute to a function?
===

    <select data-myattr="123" id="cboTest" 
            onchange="SayHello(this.data-myattr)">

This doesn't work. If I take the `data-`off of it it, it works, but from what I've read, it is html5 safe to do it that way. However, doing it that way, I get: **"Microsoft JScript runtime error: 'myattr' is undefined"**. 

This is my super-complex function:

    function SayHello(msg) {
        alert(msg);
    }

Thanks in advance.