问：

操作系统：windows98
    编程工具：vb6.0
    问题：使用ADO访问数据库时怎样判断某一表名是否存在？用DAO时，可以用TABLEDEF ,但我不想因此而走回头路,请赐教。

答：

方法1:
    Dim adoConnectionX As New ADODB.Connection
    Dim adoSchemaRecordsetX As New ADODB.Recordset
    'Ms SQL 7:
    'adoConnectionX.Open "Provider=SQLOLEDB.1;Persist Security Info=False;User ID=sa;Data Source=yuer;DataBase=NorthwindCS"
    'Access 2000:
    adoConnectionX.Open "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=E:\DRptPlus\DRptPlus\Data\NWind2K.mdb;Persist Security Info=False"
    
    Dim TestTableName As String
    TestTableName = "产品"
    
    Set adoSchemaRecordsetX = adoConnectionX.OpenSchema(adSchemaTables, Array(Empty, Empty, TestTableName, "Table"))
    
    If Not adoSchemaRecordsetX.EOF Then
     MsgBox "[" & TestTableName & "]表已存在!"
    End If
    
    
    方法2(引用Microsoft ADO Extensions 2.1 for DDL and Security (ADOX)):
    （主持人注：需要升级至VB 6.0SP3）
    Dim adoConnectionX As New ADODB.Connection
    'Ms SQL 7:
    adoConnectionX.Open "Provider=SQLOLEDB.1;Persist Security Info=False;User ID=sa;Data Source=yuer;DataBase=NorthwindCS"
    'Access 2000:
    'adoConnectionX.Open "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=E:\DRptPlus\DRptPlus\Data\NWind2K.mdb;Persist Security Info=False"
    
    Dim adoxCatalogX As New ADOX.Catalog
    Set adoxCatalogX.ActiveConnection = adoConnectionX
    
    Dim TestTableName As String
    TestTableName = "产品"
    
    Dim adoxTableX As ADOX.Table
    For Each adoxTableX In adoxCatalogX.Tables
     If adoxTableX.Name = TestTableName Then
     MsgBox "[" & TestTableName & "]表已存在!"
     Exit For
     End If
    Next
    
    主持人注：方法2也可以这样：
    Private Sub Command1_Click()
    Dim cat As ADOX.Catalog
    Dim tbl As ADOX.Table
    
    Set cat = New ADOX.Catalog
    Set cat.ActiveConnection = "Provider=Microsoft.Jet.OLEDB.3.51;" _
    & "Data Source=C:\Program Files\Microsoft Visual Studio\VB98\Biblio.mdb"
    On Error Resume Next
    Set tbl = cat.Tables("MyTable")
    
    If tbl Is Nothing Then
     MsgBox "MyTable doesn't exist"
    Else
     MsgBox "MyTable exists"
     Set tbl = Nothing
    End If
    
    Set cat = Nothing
    Set con = Nothing
    End Sub

其它方法：

select * from sysobjects where name='TblName'
    if rst.recordcount=0 then
     不存在此表
    else
     存在
    end if