Question

哪位高手给分析一下下面VB中连接数据库的问题？

'ActiveX DLL的启动程序，为DLL初始化时执行
Public Sub DBMain()
g_DBPath = App.Path & "\DB\Merchandise.mdb"

If ConnectToDatabase(DBSQLServer) = False Then
Err.Raise vbObjectError + 1, , "连接数据库出错！"
End If
End Sub
Public Function ConnectString() _
As String
'returns a DB ConnectString
ConnectString = "FileDSN=merchandise.dsn;UID=sa;PWD="
End Function
'连接到数据库
Public Function ConnectToDatabase(DBType As gxcDBType) As Boolean
On Error GoTo ERR_CONN
Set g_Conn = New Connection

'设置服务器名称，数据库名称，登录名（此时假设密码为空）
Dim ServerName As String, DBName As String, UserName As String, strPwd As String
'这些是为连接Sql Server而用
ServerName = "localhost"
DBName = "Merchandise"
UserName = ""
strPwd = ""

'连接到数据库
With g_Conn
.CursorLocation = adUseClient
.CommandTimeout = 10

If DBType = DBAccess Then
' 连接到ACCESS数据库
.ConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;Password='';" & _
"Data Source=" & g_DBPath
Else
' 连接到SQL Server数据库
.ConnectionString = ConnectString()

End If
.Open
End With
ConnectToDatabase = True
Exit Function

ERR_CONN:
ConnectToDatabase = False

End Function

'替换字符串中的单引号
Public Function RealString(strOrigional) As String
RealString = Replace(strOrigional, "'", "''")
End Function

'得到某个数据表中主键的下一个值，即当前主键值加1
Public Function NextID(ByVal strTable As String, ByVal strId As String) As Long
'两个参数分别是表的名称与主键的名称
Dim rs As Recordset
Set rs = g_Conn.Execute("SELECT MAX(" & strId & ") FROM " & strTable)

If IsNull(rs(0)) Then
'如果值为NULL，则说明无任何数据记录，此时ID应为1
NextID = 1
Else
'使新ID为最大ID值+1
NextID = rs(0).Value + 1
End If
End Function

Answer 1

错误提示是什么提示？找不到数据库？还对象变量和with变量未定义？

追问

对象变量和with变量未定义QQ1250436259

追答

对象变量和with变量未定义
这个错误就是 你的sql查询语句错了！你好好检查一下（核对一下你数据里的表记录）
好好检查一下这条语句
Set rs = g_Conn.Execute("SELECT MAX(" & strId & ") FROM " & strTable)
strId的值？
strTable的值？
from的前后加空格

追问

If ConnectToDatabase(DBSQLServer) 中把DBSQLServer改为DBaccess就是正确的，我想改用SQL2000就不正确了

追答

DBSQLServer改为DBaccess的话
把
ConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;Password='';" & _
"Data Source=" & g_DBPath
改成连接sql的语句。
ConnectionString = "Provider = "SQLOLEDB.1;Password=SQL Server密码;Persist Security Info=True;User ID=SQL Server用户名;Initial Catalog=数据库名;Data Source=服务器名或IP" "

追问

依然连不上，不过还是要谢谢你啊！

Answer 2

格式：Err.Raise vbObjectError + 513, "MyProj.MyObject ", "N>100 ", "c:\MyProj\MyHelp.Hlp ", MyContextID
Err.Raise vbObjectError + 1, ,
多了一个逗号
或者你在添加点