教学成绩管理系统的VB实现分解.ppt

一、模板 Public HostName As String 连接主机(服务器名)： Public UserName As String 用户名 Public LoginUserName As String 登录名 Public ConnectUserName As String 连接用户名 Public ConnectPassWord As String 连接用户口令 Public txtSQL As String SQL查询语句 Public msg_Sql As String SQL查询返回信息，返回结果：记录集(Recordset) Sub Main() HostName = (local) frmLogin.Show End Sub SQL Server 数据库 Public Function ConnectString() As String ConnectString = driver={SQL Server};SERVER= HostName _ ;DATABASE=产品系统销售表;UID= ConnectUserName ;PWD= ConnectPassWord End Function Public Function ExecuteSQL(ByVal SQL As String, MsgString As String) As ADODB.Recordset 传递参数：SQL 传递查询语句，MsgString传递查询信息，返回执行结果记录集 Recordset Dim cnn As ADODB.Connection 定义连接 Dim rst As ADODB.Recordset 定义返回结果：记录集 Dim sTokens() As String 定义字符串 On Error GoTo ExecuteSQL_Error sTokens = Split(SQL) Set cnn = New ADODB.Connection cnn.Open ConnectString If InStr(INSERT,DELETE,UPDATE, UCase$(sTokens(0))) Then cnn.BeginTrans cnn.Execute SQL cnn.CommitTrans MsgString = sTokens(0) 查询成功 Else Set rst = New ADODB.Recordset rst.Open Trim$(SQL), cnn, adOpenKeyset, adLockOptimistic Set ExecuteSQL = rst MsgString = 查询到 rst.RecordCount 条记录 End If ExecuteSQL_Exit: Set rst = Nothing Set cnn = Nothing Exit Function ExecuteSQL_Error: MsgString = 查询错误: Err.Description Resume ExecuteSQL_Exit End Function 二、欢迎界面 代码 1 Private Sub Form_Click() Unload Me frmLogin.Show End Sub 2 Private Sub Form_KeyPress(KeyAscii As Integer) Unload Me frmLogin.Show End Sub 3 Private Sub Image1_Click() Unload Me frmLogin.Show End Sub 4 Private Sub Timer1_Timer() Unload Me frmLogin.Show End Sub 三、登录界面 代码 Private Sub Form_Load() Me.Caption = 欢迎您 End Sub 1 Private Sub cmdOK_Click() LoginSucceeded = False