通过AJAX将文件发送到PHP

I have got this in my index.php

if (isset($_POST['PostSubm'])) {
    $file=$_FILES['ImageTi'];
        $file_name=$file['name'];
        $file_tmp=$file['tmp_name'];
        $file_size=$file['size'];
        $file_error=$file['error'];
        $file_extension=explode('.', $file_name);
        $file_extension=strtolower(end($file_extension));
        $allowed=array('jpg','png');
        if (in_array($file_extension, $allowed)) {
            if ($file_error===0) {
                if ($file_size<=2097152) {
                    $file_new_name=generateRandomString(15).rand(0,100).'.'.$file_extension;
                    $_SESSION['file_new_name']=$file_new_name;
                    $file_destination='../uploads/'.$file_new_name;
                    if (!move_uploaded_file($file_tmp,$file_destination)) {
                    echo "<p class='filerror'>Error</p>";
                    exit();
                    }
                }
            }
        }
    }

And this HTML

<form method="post" class="Postshf" enctype="multipart/form-data">
                <input type="file" name="ImageTi" id="PhotoPost">
                <textarea name="Text" placeholder="Your text here" maxlength="400"  class="descrp"></textarea>
                <input type="submit" name="PostSubm" class="PostSub" value="Post">
            </form>

And i have also got this in my jquery.js

        $(".Postshf").submit(function(){
            var descrp=$(".descrp").val();
            var s=$(".sasa").text();
            $.ajax({
                type: "GET",
                url: '../files/connect.php',
                data: "Namess="+names+"&Left="+left+"&top="+top+"&d="+descrp+"&r="+s,
                 success: function(data)
                {
                        alert(data);
                }
            });
        });

So my goal is to move file that was uploaded to "ImageTi" and at the same time insert the name of that file to database.But i am having no luck