Question

Something wierd is happening in my javascript and i dont understand it. Can anyone explain?

var adsl2pSpeed = '9500 - 12500';

        alert(adsl2pSpeed);

        if (!adsl2pSpeed) {
            alert(adsl2pSpeed);
            var adsl2pSpeed = 'Unknown';
        }


        var speed = document.getElementById("PredictedSpeed");
        speed.innerHTML = adsl2pSpeed + " b/s";

This alerts “Undefined” twice and sets the innerhtml to be “Unknown”. If I comment out the if statment it alerts ‘9500 – 12500’ and sets the innerHTML to be ‘9500 – 12500’. Whats happening? Is the string is being cast as an object so it becomes null?

EDIT : I am actually registing the adsl2pSpeed as a startup script not in the function. I moved it up for clarity but possibly that is the problem?

Answer 1

Speculation:

The indented code is in a function.

   if (!adsl2pSpeed) {
        alert(adsl2pSpeed);
        var adsl2pSpeed = 'Unknown';
    }

You are in that function declaring a local variable, which masks the global variable, so it looks “undefined”.

Try to remove the var to avoid making a new variable.