public bool Valid() { errorProvider1.Clear(); bool a = textBoxCode.Text == "" && !r_grn.IsAutoNumber(); bool b = employeeKryptonComboBox.SelectedItem == null; bool k = supplierkryptonComboBox.SelectedItem == null; bool e = false; bool f = m_do.ID > 0 ? false : r_grn.IsCodeExist(textBoxCode.Text); if (a) { errorProvider1.SetError(textBoxCode, "Code Can not Empty"); } if (b) { errorProvider1.SetError(employeeKryptonComboBox, "Employee Can not Empty"); } if (k) { errorProvider1.SetError(supplierkryptonComboBox, "Customer Can not Empty"); } if (f) { errorProvider1.SetError(textBoxCode, a ? "Code Can not Empty & Code already used" : "Code already used"); } int j = 0; for (int i = 0; i < itemsDataGrid.Rows.Count; i++) { SalesOrderItem pi = (SalesOrderItem)itemsDataGrid[scanColumn.Index, i].Tag; if (pi == null) { continue; } Part p = (Part)itemsDataGrid[codeColumn.Index, i].Tag; if (p == null) { continue; } if (itemsDataGrid[unitColumn.Index, i].Value == null) { itemsDataGrid.Rows[i].ErrorText = "Please choose unit."; e = true; } //if (itemsDataGrid[warehouseColumn.Index, i].Value == null) //{ // itemsDataGrid.Rows[i].ErrorText = "Please choose warehouse."; // e = true; //} double qty = Convert.ToDouble(itemsDataGrid[QtyColumn.Index, i].Value); if (qty == 0) { itemsDataGrid.Rows[i].ErrorText = itemsDataGrid.Rows[i].ErrorText + " Quantity must not 0(zero)"; e = true; } j++; } bool g = j == 0; if (g) { errorProvider1.SetError(itemsDataGrid, "Items must at least 1(one)"); } return(!a && !b && !e && !f && !g); }