Javascript return value undefined
Question
I would like to ask how to return variable 'get_cookies' from function 'save_value'. Then write its value in mouseleave event.
Function 'get_cookies' will save change from input. An error is in return i think.
Sorry for my bad English.
Here is code:
<html>
<head>
<script src="http://code.jquery.com/jquery-latest.min.js" type="text/javascript"></script>
<script src="jquery.cookie.js" type="text/javascript"></script>
<script type="text/javascript">
$(document).ready(function() {
function save_value(value) {
var get_cookie = value;
return get_cookie;
};
$('#submit_value').live('click', function() {
var get_value = $('#get_value').val();
save_value(get_value);
});
$(document).mouseleave(function() {
var create_cookie = save_value();
console.log('save: ' + create_cookie);
});
});
</script>
</head>
<body>
<input type="text" id="get_value" />
<input type="button" id="submit_value" value="Click" />
<div></div>
</body>
console log:
save: undefined
Thx for answer.
4 answers
solution1
4 ACCPTED 2012-09-17 11:51:20
the function save_value() is expecting a parameter. Since here
var create_cookie = save_value();
you're not passing a value to the function, it will return undefined , thus the variable create_cookie value is undefined too
solution2
1 2012-09-17 11:52:22
Your save_value() function requires an input parameter, so just save_value() on its own is undefined.
Did you mean to do this?
$(document).mouseleave(function() {
var get_value = $('#get_value').val();
var create_cookie = save_value(get_value);
console.log('save: ' + create_cookie);
});
solution3
1 2012-09-17 11:52:51
It's quite simple: your function function save_value(value) takes the value parameter, assigns it to a variable, and returns that variable. When you call it without parameters, like you do here: var create_cookie = save_value(); , the value argument will be undefined. Hence, the function returns undefined.
Also: using variables called cookie doesn't set a cookie. For that, you'll have to use localStorage.setItem('cookieName','cookieValue');
solution4
0 2012-09-17 11:52:47
Since you are using latest jQuery version, you should not use live() function, since it has been deprecated in jQuery 1.7.
Anyway, your issue is different. Your save_value function does nothing. Just creating a variable and returning its value. But you do not pass any arguments, so it returns default value: undefined .
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