private void button1_Click(object sender, EventArgs e)
        {
            BL.Worker worker = new BL.Worker();
            if (!(txtname.Text.Equals("") || txtOriginalPrice.Text.Equals("") || txtsellPrice.Text.Equals("") || txtCriticalQuantity.Text.Equals("") || txtAvilableQuantiity.Text.Equals(""))) {

                BL.Product product=new BL.Product(txtname.Text,Convert.ToInt32(txtAvilableQuantiity.Text),Convert.ToInt32(txtCriticalQuantity.Text),float.Parse(txtOriginalPrice.Text),float.Parse(txtsellPrice.Text));
                if(worker.AddProduct(product)){     // check product is added if added show user message box Done
                MessageBox.Show("تم اضافة المنج بنجاح");
                txtAvilableQuantiity.Text = "";
                txtCriticalQuantity.Text = "";
                txtname.Text = "";
                txtOriginalPrice.Text = "";
                txtsellPrice.Text = "";
                }
                else{                          // if prduct do not adde show user message Wrong for adding product
                MessageBox.Show("خطا فى الاضافه");
                }
            }
            else { MessageBox.Show("املا جميع الفرغات"); }   //show message box to make user write all fields
        }