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The IsConnected method of an object of ClassType clsDataSource verifies the connection to the data source specified by the ConnectionString property. If the data source is not connected, the method attempts to connect to the source.
语法
bRet = object.IsConnected(ErrorMsg As String)
参数
- bRet
A Boolean variable that receives the returned value: True is returned if the data source is connected, False if the connection cannot be established.
- object
An object of ClassTypeclsDataSource.
- ErrorMsg
An optional string variable that receives the error definition if the connection cannot be established.
备注
If the data source is already connected when the method is executed, the method returns True. If the data source is not connected, the method attempts to connect to the data source, returning True if the connection is established or False if the connection cannot be established.
It is not necessary to establish a connection to a data source before it can be used. Decision Support Objects (DSO) will automatically establish the connection when necessary (for example, to read a property value from the source database or to access data in the database).
示例
Use the following code to establish a connection to a data source with the IsConnected property:
'Assume an object (dsoDS) of ClassType clsDataSource exists
If Not dsoDS.IsConnected Then
' Code to handle connection error
Else
' Connection is established
End If
请参阅
参考
clsDataSource
ConnectionString (clsDataSource)