setInterval and window.onload problem

javascript, setinterval

Solution

Using a string command in `setInterval()` will try to look for the function in the global (window) scope, but since the function is defined in a local scope, it won't be found. You should pass the function itself to `setInterval()` instead.

window.onload = function() {            
    function foo() {
        alert("test");
    }
    setInterval(foo, 500);
}

Problem

I have this code ``` window.onload = function() { function foo() { alert("test"); } setInterval("foo()",500) } ``` Which returns undefined...When i use it outside the window.onload it works. Can anyone explain me why?

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