Why is a function declared in document.ready() not defined when called?
Question
Here is my HTML/JavaScript:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head><meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Untitled Document</title>
<script type="text/javascript" src="/script/jquery.js"></script>
<script type="text/javascript">
$(function(){
var $str = "hello world";
function foo() {
alert($str);
}
});
</script>
</head>
<body>
<form name="statusUpdateForm" method="post">
<input type="button" name="submitButton" value=" " onclick="foo();" />
</form>
</body>
</html>
When I click the button, I get a JavaScript error stating that foo is not defined. How can I call a JavaScript function declared inside document.ready()??
5 answers
solution1
7 ACCPTED 2011-05-25 19:13:29
You're placing the function's scope within another function, basically.
Picture this:
<script>
document.onload = function(){
function foo(){
alert('bar');
}
};
foo();
</script>
That is the facsimile of what you're trying to accomplish. Just like variables defined within a function are off limits outside of it, function names take on the same characteristics.
Side-Note JavaScript doesn't require $ prefix on variable names (though is acceptable as far as names are concerned). I didn't know if you're coming from PHP and are just accustomed or were aware.
Thought I'd make my comment an answer.
solution2
1 2013-01-31 08:03:14
Variables and methods declared inside the $(function() function are only accessible within that. If you need to use those outside, you you make it in the global namespace like
window.functionName = functionName;
solution3
1 2011-05-25 20:23:15
Try this:
$(function() {
window.foo = function () {
alert('bar');
}
});
Basically, you need to expose the function to global scope.
solution4
0 2011-05-25 19:11:44
You can not, it is private to that scope.
solution5
0 2011-05-28 03:15:18
What I ended up doing - what I should have done in the first place - is adding a click handler for the submit button:
$("input[name='submitButton']").click(function(){...});
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