Serial port (RS232) and barcode scan features Direct access to serial port and I/O operations Ready solution for Barcode scanner device Find all available serial ports in the system (native and virtual IrDA, USB, bluetooth COM ports) RS485 mode pass
'set the global var to false 'to denote a failed login LoginSucceeded = False Unload Me End Sub Private Sub cmdOK_Click() On Error GoTo errh: Dim rs As ADODB.Recordset Set rs = New ADODB.Recordset Set rs = cn.Execute("SELECT UserNam e , Password FRO
附登陆代码: using System; using System.Drawing; using System.Collections; using System.ComponentModel; using System.Windows.Forms; using System.Data; using System.Data.SqlClient; namespace 图书馆管理信息系统 { /// /// Form1 的摘要说明。 /// pub lic class login : Syst