private void btnAdd_Click(object sender, EventArgs e)
        {
            Addcar_Form frm = new Addcar_Form();

            frm.ShowDialog();
            this.dgGetAllCar.DataSource = Cmg.GET_ALL_CARS();
        }
        private void btnEdit_Click(object sender, EventArgs e)
        {
            Addcar_Form frm = new Addcar_Form();

            frm.cmbboxcarcategory.Text = this.dgGetAllCar.CurrentRow.Cells[0].Value.ToString();
            frm.txtcarname.Text        = this.dgGetAllCar.CurrentRow.Cells[1].Value.ToString();
            frm.txtcarprice.Text       = this.dgGetAllCar.CurrentRow.Cells[2].Value.ToString();
            frm.txtquantity.Text       = this.dgGetAllCar.CurrentRow.Cells[3].Value.ToString();
            frm.Text                = "Edit_form";
            frm.btnaccept.Text      = "modify";
            frm.state               = "update";
            frm.txtcarname.ReadOnly = true;
            byte[]       byteImage = (byte[])Cmg.Get_Imagecar(Convert.ToInt32(this.dgGetAllCar.CurrentRow.Cells[0].Value.ToString())).Rows[0][0];
            MemoryStream ms        = new MemoryStream(byteImage);

            frm.picboxcarimage.Image = Image.FromStream(ms);
            frm.ShowDialog();
            this.dgGetAllCar.DataSource = Cmg.GET_ALL_CARS();
        }
        private void addNewCarForm_Click(object sender, EventArgs e)
        {
            Addcar_Form addform = new Addcar_Form();

            addform.ShowDialog();
        }