Suppose I have the following HTML:
<form id="myform">
<input type='checkbox' name='foo[]'/> Check 1<br/>
<input type='checkbox' name='foo[]' checked='true'/> Check 2<br/>
<input type='checkbox' name='foo[]'/> Check 3<br/>
</form>
Now, how do I select the checked input fields with name 'foo[]'?
This is my try, but it doesn't work:
$('#myform input[name='foo']:checked:enabled');
The name of the field isn't foo, it is foo[]. You could use the attributeStartsWith selector:
$("input[name^='foo']:checked:enabled",'#myform');
Ideally, you'd be able to do this:
$("input[name='foo[]']:checked:enabled",'#myform');
But as this answer explains, jQuery uses this to parse the value part of the attr=value condition:
(['"]*)(.*?)\3|)\s*\]
\3 being the group containing the opening quotes, which weirdly are allowed to be multiple opening quotes, or no opening quotes at all. The .*? then can parse any character, including quotes until it hits the first ‘]’ character, ending the match. There is no provision for backslash-escaping CSS special characters, so you can't match an arbitrary string value in jQuery.
In other words, as soon as jQuery hits the first ] it thinks the value is over. So you are stuck with startsWith or using pure DOM elements, as that answer also explains.
SUPER DUPER IMPORTANT EDIT:
This bug is fixed, apparently. You should be able to use the code I described as "ideal", above.
I believe it goes something like this:
$("input #foo[] :checked");
EDIT: The commenter is right. I should have gone with my first response. :) This time I am going to use the "^".
$("input[name^=foo] :checked");
You should quote the attribute when selecting and include []:
$("#myform input[name='foo[]']:checked:enabled");
Actually, what you have works just fine, just use double quotes, and include the brackets so it can match.
$("#myform input[name='foo[]']:checked:enabled");
You can see it in action here: http://jsbin.com/oyoro
Note that jQuery has had issues on and off with brackets in the past, which can explain a lot of the confusion surrounding the need for escaping. I know I've had issue myself with brackets and just quoting.