I'm hoping someone can explain to me why the below JavaScript/HTML will show "door #2" when the HTML is viewed in a browser:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<script type="text/javascript">
function testprint() {
alert('door #1');
};
window.onload = testprint;
function testprint() {
alert('door #2');
};
testprint = function() {
alert('door #3');
};
</script>
<script type="text/javascript">
function testprint() {
alert('door #4');
};
</script>
</head>
<body>
</body>
</html>
Since only the declaration testprint occurs before window.onload is set to testprint, I would expect window.onload cause 'door #1' to show up. Actually, onload causes 'door #2'. Note that it will do this whether the first declaration of testprint is included or not.
The third and fourth declaration of testprint use different means of assigning the function, I tried this to see if it would override window.onload's behavior in the same was the second declaration of testprint does. It did not. Note that if I move the fourth declaration of testprint to the end of the first script block it would be called by window.onload.
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