module1.bas

Visual Basic程序设计基础》-杨小影-源代码

Attribute VB_Name = "Module1"
Option Explicit
Public pubCnn As New ADODB.Connection   '全局连接对象供各模块使用
Public Sub CreateConnection()
    pubCnn.CursorLocation = adUseClient
    pubCnn.Open "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=Stud05.mdb"
    
End Sub
'填充班级组合框。参数为组合框对象变量
Public Sub AddClassItem(cboX As ComboBox)
    Dim rsTmp As New ADODB.Recordset '临时记录集
     '过滤重复记录和空字段
    '方法1：利用 GROUP BY 子句
  ' rsTmp.Open "SELECT 班级 FROM 学籍 GROUP BY 班级 " & _
        " HAVING 班级<>NULL AND 班级<>''", _
        pubCnn, adOpenStatic, adLockOptimistic

    '方法2：利用 DISTINCT 关键字
   rsTmp.Open "SELECT DISTINCT 班级 FROM 学籍 " & _
        " WHERE 班级<>NULL AND 班级<>''", _
        pubCnn, adOpenStatic, adLockOptimistic
       
        
    '在组合框中添加班级
    cboX.Clear
    Do Until rsTmp.EOF
        cboX.AddItem rsTmp("班级")
        rsTmp.MoveNext
    Loop
    Set rsTmp = Nothing
End Sub