file not uploaded to the server with ajax - php

Question

This is my form source:
<form id="createProject" name="createProject" class="form-light" method="post" enctype="multipart/form-data" target="upload_target">
<div class="col-md-10" id="sandbox-container1">
<label>Project duration</label>
<div class="input-daterange input-group" id="datepicker">
<input type="text" required class="input-md form-control" id="start" name="start" />
<span class="input-group-addon">to</span>
<input type="text" required class="input-md form-control" id="end" name="end" />
</div>
</div>
<div class="col-md-10">
<div class="form-group">
<label>Project attachment's</label>
<input type="file" class="form-control" id="projectFile" name="projectFile" placeholder="Select project attachment's">
</div>
</div>
<input type="hidden" id="ownerid" name="ownerid" value="<?php echo $userid; ?>">
<div class="col-md-10">
<div class="form-group">
<button class="btn btn-two pull-right btn-lg" form="createProject" type="submit">Submit</button>
</div>
</div>
</form>
File is not uploading to the server.
I use ajax function to submit.
$.ajax({
url:'ajaxcalls/createprojectfunction.php',
data:$(this).serialize(),
type:'POST',
beforeSubmit: function()
{
/* Before submit */
for ( instance in CKEDITOR.instances )
{
CKEDITOR.instances[instance].updateElement();
}
},
success:function(data){
console.log(data);
},
error:function(data){
}
});
Firebug console this error occur.
Notice: Undefined index: projectFile.
but all other input element are accessable in ajax URL php file.

Answer 1

You'll have to use a FormData object to upload a file via ajax,
$.ajax({
url:'ajaxcalls/createprojectfunction.php',
data: new FormData(this),
type:'POST',
processData: false,
contentType: false,
beforeSubmit: function()
{
/* Before submit */
for ( instance in CKEDITOR.instances )
{
CKEDITOR.instances[instance].updateElement();
}
},
success:function(data){
console.log(data);
},
error:function(data){
}
});