private void button2_Click(object sender, EventArgs e) { if (comboBox1.SelectionLength == 0 || comboBox2.SelectionLength == 0 || textBox1.TextLength == 0 || textBox2.TextLength == 0 || textBox3.TextLength == 0 || comboBox3.SelectionLength == 0) { MessageBox.Show("Enter value"); return; } DB.addDataToEquipmentMaster(comboBox1.Text, comboBox2.Text, textBox1.Text, textBox2.Text, textBox3.Text, comboBox3.Text); loadInfoToTable(); }