// add new product button, shows the form for adding new product "frm_addProduct"
        private void button1_Click(object sender, EventArgs e)
        {
            frm_addProduct f = new frm_addProduct();

            // pass this form by reference to another form to make the other form control this form
            // which is used to refresh this form after adding a new product from the "add new product" form
            f.setMngProdctsVar = this;

            f.ShowDialog();
        }
        private void edtSlctdPrdct_Click(object sender, EventArgs e)
        {
            frm_addProduct f = new frm_addProduct();

            f.Text                       = "تحديث بيانات : " + this.dgvProductsLst.CurrentRow.Cells[1].Value.ToString();
            f.txtProdName.Text           = this.dgvProductsLst.CurrentRow.Cells[1].Value.ToString();
            f.txtProductNotes.Text       = this.dgvProductsLst.CurrentRow.Cells[4].Value.ToString();
            f.alrtQntnumericUpDown.Value = Convert.ToInt32(this.dgvProductsLst.CurrentRow.Cells[3].Value);
            f.cmbSplrs.Text              = this.dgvProductsLst.CurrentRow.Cells[5].Value.ToString();
            f.cmbCats.Text               = this.dgvProductsLst.CurrentRow.Cells[6].Value.ToString();
            f.cmbMsrUnt.Text             = f.textBox1.Text = this.dgvProductsLst.CurrentRow.Cells[7].Value.ToString();
            f.btnAddProduct.Text         = "تحديث";

            f.pictureBox1.Image = productImg.Image;

            // change the state of the form to update state, Default state: add
            f._formState       = "update";
            f._productIDToUpdt = Convert.ToInt16(this.dgvProductsLst.CurrentRow.Cells[0].Value.ToString());

            f.ShowDialog();
        }
        private void addNewProductToolStripMenuItem_Click(object sender, EventArgs e)
        {
            frm_addProduct f = new frm_addProduct();

            f.ShowDialog();
        }