How do I use jQuery's form.serialize but exclude empty fields

Tom Viner picture Tom Viner · Mar 4, 2009 · Viewed 86.4k times · Source

I have a search form with a number of text inputs & drop downs that submits via a GET. I'd like to have a cleaner search url by removing the empty fields from the querystring when a search is performed.

var form = $("form");  
var serializedFormStr = form.serialize();  
// I'd like to remove inputs where value is '' or '.' here
window.location.href = '/search?' + serializedFormStr

Any idea how I can do this using jQuery?

Answer

Tom Viner picture Tom Viner · Mar 4, 2009

I've been looking over the jQuery docs and I think we can do this in one line using selectors:

$("#myForm :input[value!='']").serialize() // does the job!

Obviously #myForm gets the element with id "myForm" but what was less obvious to me at first was that the space character is needed between #myForm and :input as it is the descendant operator.

:input matches all input, textarea, select and button elements.

[value!=''] is an attribute not equal filter. The weird (and helpful) thing is that all :input element types have value attributes even selects and checkboxes etc.

Finally to also remove inputs where the value was '.' (as mentioned in the question):

$("#myForm :input[value!=''][value!='.']").serialize()

In this case juxtaposition, ie placing two attribute selectors next to each other, implies an AND. Using a comma implies an OR. Sorry if that's obvious to CSS people!