.submit() without reloading page - php

Question

I am trying do some file upload using jquery. The upload box have to be in the dialog box.
Now I just want to know after I click on the dialog's upload button. How can I submit yet the page do not load.
I tried using this
$('#uploadForm').submit().preventDefault();
It has not action at all.
html
<script>
$( "#dialog-upload" ).dialog({
autoOpen: false,
height: 200,
width: 350,
modal: true,
buttons: {
"Upload": function() {
var bValid = true;
bValid = bValid && checkCSV()
if(bValid){
**$('#uploadForm').submit().preventDefault();**
}
$( "#dialog-upload" ).dialog( "close" );
},
Cancel: function() {
allFields.val( "" ).removeClass( "ui-state-error" );
$( this ).dialog( "close" );
}
},
close: function() {
allFields.val( "" ).removeClass( "ui-state-error" );
$( this ).dialog( "close" );
}
});
</script>
<div id="dialog-upload" title="Upload csv file">
<form>
<fieldset>
<form action='ajax.php' id = 'uploadForm' method='post' enctype='multipart/form-data'>
<input type="text" name="file" id="fileUpload" size = 30 class="text ui-corner-all" />
</form>
</fieldset>
</form>
</div>
php
if (isset($_FILES['file'])) {
echo "success";
}

Answer 1

Use the EVENT delegation for your form submit
$('#uploadForm').submit(function( e ){
e.preventDefault(); // browser 'submit' event behavior prevented
});
Than do:
"Upload": function() {
var bValid = true;
bValid = bValid && checkCSV()
if(bValid){
$('#uploadForm').submit();
}
// ......

Answer 2

You can bind something to the submit event prior to submitting.
$(function() {
$('#uploadForm').submit(function(evt) {
evt.preventDefault();
});
});
Then just call .submit() without the preventDefault() in your original location.