Disable zero as first letter in <input>

Question

Below code disables 0 as the first character in #foo.
However, you can bypass this by typing 123, then drag to select 123

Answer 1

Here's the fixed version :

$('input#foo').keyup(function(e){ 
     if(this.value.substring(0,1) == "0")
     {
        this.value = this.value.replace(/^0+/g, '');             
     }         
});

jsfiddle : http://jsfiddle.net/ewmb1yq9/4/