jQuery create object from form fields

var inputs = $("form :input");
var obj = $.map(inputs, function(x, y) {
    return {
        Key: x.name,
        Value: $(x).val()
    };
});
console.log(obj);

You can do this:

var fields = {};
$("#theForm").find(":input").each(function() {
    // The selector will match buttons; if you want to filter
    // them out, check `this.tagName` and `this.type`; see
    // below
    fields[this.name] = $(this).val();
});
var obj = {fields: fields}; // You said you wanted an object with a `fields` property, so...

Beware that forms can have fields with repeated names, and what you're trying to do doesn't support that. Also, the order of fields in HTML forms can be significant. (These are both reasons that serializeArray works the way it does.)

Note that normal HTML practice is to omit disabled fields. If you want to do that, check this.disabled before grabbing the value as well.

---

Note that the above (written two years ago) uses a jQuery pseudo-selector. I'm a bit surprised to find that I wrote that. As it says in the documentation for the :input pseudo-selector, using it means that jQuery can't hand off the selector to the browser's native querySelectorAll (which nearly all browsers now have).

Nowadays I'd probably write:

$("#theForm").find("input, textarea, select, button")...

...if I wanted buttons, or if not then

$("#theForm").find("input, textarea, select")...

...and then filter out input[type="button"] and input[type="submit"] inside the each. E.g. (no buttons at all):

$("#theForm").find("input, textarea, select").each(function() {
    var inputType = this.tagName.toUpperCase() === "INPUT" && this.type.toUpperCase();
    if (inputType !== "BUTTON" && inputType !== "SUBMIT") {
        // ...include it, either it's an `input` with a different `type`
        // or it's a `textarea` or a `select`...
    }
});