Input string was not in a correct format.

<script language="javascript" type="text/javascript">
        $(document).ready(function () {
            $('#<%=imgToCrop.ClientID%>').Jcrop({
                onSelect: getAreaToCrop
            });
        });
        function getAreaToCrop(c) {
            $('#XCoordinate').val(parseInt(c.x));
            $('#YCoordinate').val(parseInt(c.y));
            $('#Width').val(parseInt(c.w));
            $('#Height').val(parseInt(c.h));
        }
    </script>

protected void btnCrop_Click(object sender, EventArgs e)
    {
        string croppedFileName = string.Empty;
        string croppedFilePath = string.Empty;
        string fileName = Path.GetFileName(imgToCrop.ImageUrl);
        string filePath = Path.Combine(Server.MapPath("~/uploads"), fileName);
        if (File.Exists(filePath))
        {

            System.Drawing.Image orgImg = System.Drawing.Image.FromFile(filePath);
            Rectangle areaToCrop = new Rectangle(
                Convert.ToInt32(XCoordinate.Value),
                Convert.ToInt32(YCoordinate.Value),
                Convert.ToInt32(Width.Value),
                Convert.ToInt32(Height.Value));
            try
            {

                Bitmap bitMap = new Bitmap(areaToCrop.Width, areaToCrop.Height);
                using (Graphics g = Graphics.FromImage(bitMap))
                {
                    g.DrawImage(orgImg, new Rectangle(0, 0, bitMap.Width, bitMap.Height), areaToCrop, GraphicsUnit.Pixel);
                }
                croppedFileName = "crop_" + fileName;
                croppedFilePath = Path.Combine(Server.MapPath("~/uploads"), croppedFileName);
                bitMap.Save(croppedFilePath);
                orgImg.Dispose();
                bitMap = null;
                File.Delete(filePath);

                pnlCrop.Visible = false;
                lblMsg.ForeColor = Color.Green;
                lblMsg.Text = "Image cropped and saved successfully";

                imgCropped.ImageUrl = "~/uploads/" + croppedFileName;
                btnReset.Visible = true;

                string avater_path = "uploads/" + croppedFileName;
                myProfile objPr_dal = new myProfile();
                string userId = Convert.ToString(Session["Userid"]);
                int result = objPr_dal.Set_user_avater(userId, avater_path);

                if (result == 1)
                {
                    Response.Redirect("profile.aspx");
                }

            }
            catch (Exception ex)
            {
                lblMsg.Text = "Oops!! error occured : " + ex.Message.ToString();
            }
            finally
            {
                fileName = string.Empty;
                filePath = string.Empty;
                croppedFileName = string.Empty;
                croppedFilePath = string.Empty;
            }
        }


when i click crop button error is occured/hit here,,
               Rectangle areaToCrop = new Rectangle(
                Convert.ToInt32(XCoordinate.Value),
                Convert.ToInt32(YCoordinate.Value),
                Convert.ToInt32(Width.Value),
                Convert.ToInt32(Height.Value));