What's the easiest way to do form validation for jQuery?

Question

All I want to do is to check if the textfield has been changed. If not, I want to highlight the boxes when submit is pressed. How do I do that? Seems very simple, but not sure why every other solution is so complicated.

Answer 1

Building upon Pim's answer, you can associate the changed flag for each text field using jQuery's data API.

// initially, assign changed to false for all text fields
$("input:text").data("changed", false);

// if any field changes, set its changed flag to true
$("input:text").change(function() {
    $(this).data("changed", true);
}

// finally on submission, get all text fields that did not
//  change by checking their "changed" property
var unchangedItems = $("input:text").filter(function() {
    return $(this).data("changed") === false;
});

Answer 2

您可以使用jQuery 验证插件。

Answer 3

Bassicly, you just say it has never been changed, and when it cahnges, you set a flag saying is has been changed:

var changed = false;
$('#textfield').change(function(){
    changed = true;
});
if(changed){
    $('.textbox').each(function(){
        $(this).addClass('.highlighted');
        //or something like this, whatever you want to do to highlight them
    });
}