private void butadd_Click(object sender, EventArgs e)
        {
            supplier supp = new supplier();

            if (state == "Add")
            {
                if (text_Sup_ID.Text == string.Empty || textsupName.Text == string.Empty || textSupphone.Text == string.Empty ||
                    Cmb_company.Text == string.Empty || textSupaddress.Text == string.Empty)
                {
                    MessageBox.Show("Rewrite all data !", "Attention", MessageBoxButtons.OK, MessageBoxIcon.Information);
                    return;
                }
                clsssup.AddSupplier(textsupName.Text, textSupphone.Text, textSupemail.Text,
                                    Cmb_company.Text, textSupaddress.Text, DateSupplier.Value, text_user_add.Text);
                MessageBox.Show("Add Supplier Done Successfuly", "SMMS", MessageBoxButtons.OK, MessageBoxIcon.Information);
                butadd.Enabled = false;
                butnew.Enabled = true;
                clear();
                textsupName.Enabled    = false;
                textSupphone.Enabled   = false;
                textSupemail.Enabled   = false;
                textSupaddress.Enabled = false;
            }

            else
            {
                if (text_Sup_ID.Text == string.Empty || textsupName.Text == string.Empty || textSupphone.Text == string.Empty ||
                    Cmb_company.Text == string.Empty || textSupaddress.Text == string.Empty)
                {
                    MessageBox.Show("Rewrite all data !", "Attention", MessageBoxButtons.OK, MessageBoxIcon.Information);
                    return;
                }
                clsssup.UpdateSupplier(Convert.ToInt32(text_Sup_ID.Text), textsupName.Text, textSupphone.Text, textSupemail.Text,
                                       Cmb_company.Text, textSupaddress.Text, DateSupplier.Value, text_user_add.Text);
                MessageBox.Show("Edit Supplier Done Successfuly", "SMMS", MessageBoxButtons.OK, MessageBoxIcon.Information);

                clear();
                this.Close();
            }
            supplier_management.getmainform.dataGridView1.DataSource = clsssup.GET_ALL_Supplier();
        }
        private void button2_Click(object sender, EventArgs e)
        {
            supplier Sup = new supplier();

            Sup.butadd.Enabled         = true;
            Sup.butnew.Visible         = false;
            Sup.textsupName.Enabled    = true;
            Sup.textSupphone.Enabled   = true;
            Sup.textSupemail.Enabled   = true;
            Sup.textSupaddress.Enabled = true;

            Sup.text_Sup_ID.Text    = this.dataGridView1.CurrentRow.Cells[0].Value.ToString();
            Sup.textsupName.Text    = this.dataGridView1.CurrentRow.Cells[1].Value.ToString();
            Sup.textSupphone.Text   = this.dataGridView1.CurrentRow.Cells[2].Value.ToString();
            Sup.textSupemail.Text   = this.dataGridView1.CurrentRow.Cells[3].Value.ToString();
            Sup.textSupaddress.Text = this.dataGridView1.CurrentRow.Cells[5].Value.ToString();
            Sup.text_user_add.Text  = this.dataGridView1.CurrentRow.Cells[7].Value.ToString();
            Sup.Text        = "Supplier Update:" + this.dataGridView1.CurrentRow.Cells[1].Value.ToString();
            Sup.butadd.Text = "Update";
            Sup.state       = "update";
            Sup.ShowDialog();

            Sup.Close();
        }
        private static supplier frmsup;                                        //  ......................[1]

        static void frm_formclosed(object sender, FormClosedEventArgs e)       //  ................[2]
        {
            frmsup = null;
        }
        private void button1_Click(object sender, EventArgs e)
        {
            supplier suplier = new supplier();

            suplier.ShowDialog();
        }
        private void addNewSuppliersToolStripMenuItem_Click(object sender, EventArgs e)
        {
            supplier frm = new supplier();

            frm.ShowDialog();
        }