jQuery: how do I return true if any checkbox is selected in an array of checkboxes?

my checkboxs each 开发者_如何学Clook like this:

<input id="bulk_selected_" name="bulk_selected[]" type="checkbox" value="159">

Use an attribute-equals selector and .is(), like this:

return $("input[name='bulk_selected[]']").is(":checked");
//or...
return $("input[name='bulk_selected[]']:checked").length;

.is() will return true is any of the elements match the selector. Or a bit faster version:

return $("input[name='bulk_selected[]']").filter(function() { 
  return this.checked; 
}).length > 0;

return jQuery('[name="bulk_selected[]"]:checked').size()

If none are checked, then it will return 0 (a false value) otherwise it will return a positive number (which will be true).