VB应用程序访问SQL Server的常用方法

Public Function SQLExistDatabase
(Cn As ADODB.Connection, sDBName As String) 
As Boolean  
Dim sSQL As String  
Dim RS As New ADODB.Recordset  
Dim bTmp As Boolean  
on Error GoTo errSQLExistDatabase  
sSQL = "select CntDB = count ( * ) "  
sSQL = sSQL & "From master.dbo.sysdatabases"  
sSQL = sSQL & "Where name = 注释： "& sDBName & " 注释： "

RS.Open sSQL, Cn  
If RS! CntDB = 0 Then bTmp = False Else bTmp = True  
RS.Close  
SQLExistDatabase = bTmp  
Exit Function  
errSQLExistDatabase:  
SQLExistDatabase = False  
Exit Function  
End Function

Public Function SQLDropDatabase 
(Cn As ADODB.Connection, sDBName As String) As Boolean
Dim sSQL As String  
On Error GoTo errSQLDropDatabase  
If Not SQLExistDatabase(Cn, sDBName) Then  
SQLDropDatabase = True  
Exit Function  
End If  
Dim sDB As String  
sDB = SQLGetCurrentDatabaseName(Cn)  
sSQL = "Use master" 
Cn.Execute sSQL  
sSQL = "DROP DATABASE " & sDBName  
Cn.Execute sSQL 
sSQL = "USE " & sDB  
Cn.Execute sSQL  
SQLDropDatabase = True  
Exit Function  
errSQLDropDatabase:  
On Error Resume Next  
sSQL = "USE " & sDB  
Cn.Execute sSQL  
SQLDropDatabase = False  
End Function