Serialize form data to JSON [duplicate]

Answer 1

Trying to solve the same problem (validation without getting into complex plugins and libraries), I created jQuery.serializeJSON, that improves serializeArray to support any kind of nested objects.

This plugin got very popular, but in another project I was using Backbone.js, where I would like to write the validation logic in the Backbone.js models. Then I created Backbone.Formwell, which allows you to show the errors returned by the validation method directly in the form.

Answer 2

Use:

var config = {};
jQuery(form).serializeArray().map(function(item) {
    if ( config[item.name] ) {
        if ( typeof(config[item.name]) === "string" ) {
            config[item.name] = [config[item.name]];
        }
        config[item.name].push(item.value);
    } else {
        config[item.name] = item.value;
    }
});

Answer 3

If you are sending the form with JSON you must remove [] in the sending string. You can do that with the jQuery function serializeObject():

var frm = $(document.myform);
var data = JSON.stringify(frm.serializeObject());

$.fn.serializeObject = function() {
    var o = {};
    //    var a = this.serializeArray();
    $(this).find('input[type="hidden"], input[type="text"], input[type="password"], input[type="checkbox"]:checked, input[type="radio"]:checked, select').each(function() {
        if ($(this).attr('type') == 'hidden') { //if checkbox is checked do not take the hidden field
            var $parent = $(this).parent();
            var $chb = $parent.find('input[type="checkbox"][name="' + this.name.replace(/\[/g, '\[').replace(/\]/g, '\]') + '"]');
            if ($chb != null) {
                if ($chb.prop('checked')) return;
            }
        }
        if (this.name === null || this.name === undefined || this.name === '')
            return;
        var elemValue = null;
        if ($(this).is('select'))
            elemValue = $(this).find('option:selected').val();
        else elemValue = this.value;
        if (o[this.name] !== undefined) {
            if (!o[this.name].push) {
                o[this.name] = [o[this.name]];
            }
            o[this.name].push(elemValue || '');
        } else {
            o[this.name] = elemValue || '';
        }
    });
    return o;
}

Answer 4

Using jQuery and avoiding serializeArray, the following code serializes and sends the form data in JSON format:

$("#commentsForm").submit(function(event){
    var formJqObj = $("#commentsForm");
    var formDataObj = {};
    (function(){
        formJqObj.find(":input").not("[type='submit']").not("[type='reset']").each(function(){
            var thisInput = $(this);
            formDataObj[thisInput.attr("name")] = thisInput.val();
        });
    })();
    $.ajax({
        type: "POST",
        url: YOUR_URL_HERE,
        data: JSON.stringify(formDataObj),
        contentType: "application/json"
    })
    .done(function(data, textStatus, jqXHR){
        console.log("Ajax completed: " + data);
    })
    .fail(function(jqXHR, textStatus, errorThrown){
        console.log("Ajax problem: " + textStatus + ". " + errorThrown);
    });
    event.preventDefault();
});

Answer 5

Here's a function for this use case:

function getFormData($form){
    var unindexed_array = $form.serializeArray();
    var indexed_array = {};

    $.map(unindexed_array, function(n, i){
        indexed_array[n['name']] = n['value'];
    });

    return indexed_array;
}

Usage:

var $form = $("#form_data");
var data = getFormData($form);

Answer 6

Here is what I use for this situation as a module (in my formhelper.js):

define(function(){
    FormHelper = {};

    FormHelper.parseForm = function($form){
        var serialized = $form.serializeArray();
        var s = '';
        var data = {};
        for(s in serialized){
            data[serialized[s]['name']] = serialized[s]['value']
        }
        return JSON.stringify(data);
    }

    return FormHelper;
});

It kind of sucks that I can't seem to find another way to do what I want to do.

This does return this JSON for me:

{"first_name":"John","last_name":"Smith","age":"30"}