how to prevent form submission in case of valiadtion error with standard form submission?

Question

I am developing a form that which includes some textfields and some fields for file uploads. Some javascript code builds the form dynammically by adding it to to a div element (id=wrapper). To my knowlegde one cannot send/upload files via ajax, so I choose the 'classic way' to post the form, see code below. However, I want to have the textfields validated by means of jquery validate; the validation code works fine, but how to prevent the form submission in case of a validation error?. I assume I need somehow to override the standard form submission handler, but dont know how to do that...

//original form submit code
$("#formNewAgreements").submit(function(){
var form = $("#formNewAgreements");

form.validate();
if(form.valid()){ //only submit via ajax if javascript validation has been performed successfully
    $.ajax({
        type: "POST",
        url: "suppladmin_agreementsetup_submit_x1.php",
        data: $("#formNewAgreements").serialize(),
        dataType: "json",

        success: function(msg){
        if(msg.statusgeneral == 'success'){
            $("#wrapper").children().remove(); //remove current New Agreements form
            SetupAgreements();
        }
        else
        {
           $("#errorbox").html(msg.statusgeneral);

        }//else
        }, //succes: function   
        error: function(){
    $("#errorbox").html("There was an error submitting the form. Please try again.");
        }
    });//.ajax

//make sure the form doesn't post
return false;
} //if(form.valid()

});//$("#myForm").submit()


//validation code for validing the textfields
var completeform = $("#formNewAgreements");
completeform.validate();

//html code form
<form id="formNewAgreements" name="formNewAgreements" action="submit_x1.php" method="post" enctype="multipart/form-data" target="hidden-form" >
<!--<form id="formNewAgreements" name="formNewAgreements" action="" method="post" autocomplete="on">-->
    <a href="#" id="add-form">Add agreement</a>
    <div id="wrapper"></div> <!--anchor point for adding set of form fields -->   
    <input type="hidden" name="form_token" value="<?php echo $form_token; ?>" />
    <input type="submit" name="submitForm" value="Confirm">
</form>
<iframe style="display:inline" name="hidden-form" width="200" height="20"></iframe>

Answer 1

Quote OP:

"I want to have the textfields validated by means of jquery validate"

Since you're using the jQuery Validate plugin, simply implement the submitHandler callback for your ajax . As per documentation , this is "the right place to submit a form via Ajax after it is validated" .

Despite others' answers,

• You do not need inline JavaScript.

• You do not need any additional event handlers.

var completeform = $("#formNewAgreements");
completeform.validate({
    submitHandler: function(form) {
        // your ajax here
        return false;  // block default form action
    }
});

DEMO: http://jsfiddle.net/U4P3F/

Answer 2

Try this

<input type="submit" name="submitForm" value="Confirm" onclick='completeform.validate();' />

In this case your validate method should return true or false depending on if form is valid or not.

EDIT: As @lex82 mentioned the proper way to do this is to add handler to form submit. Change you form tag to:

<form id="formNewAgreements" name="formNewAgreements" action="submit_x1.php" method="post" enctype="multipart/form-data" target="hidden-form" onsubmit='completeform.validate();'>