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CDataSource::Open

Opens a connection to a data source using a CLSID, ProgID, or CEnumerator moniker or prompts the user with a locator dialog box.

HRESULT Open(
   const CLSID& clsid,
   DBPROPSET* pPropSet = NULL,
   ULONG nPropertySets = 1 
) throw( );
HRESULT Open(
   const CLSID& clsid,
   LPCTSTR pName,
   LPCTSTR pUserName = NULL,
   LPCTSTR pPassword = NULL,
   long nInitMode = 0 
) throw( );
HRESULT Open(
   LPCTSTR szProgID,
   DBPROPSET* pPropSet = NULL,
   ULONG nPropertySets = 1 
) throw( );
HRESULT Open(
   LPCTSTR szProgID,
   LPCTSTR pName,
   LPCTSTR pUserName = NULL,
   LPCTSTR pPassword = NULL,
   long nInitMode = 0 
) throw( );
HRESULT Open(
   const CEnumerator& enumerator,
   DBPROPSET* pPropSet = NULL,
   ULONG nPropertySets = 1 
) throw( );
HRESULT Open(
   const CEnumerator& enumerator,
   LPCTSTR pName,
   LPCTSTR pUserName = NULL,
   LPCTSTR pPassword = NULL,
   long nInitMode = 0 
) throw( );
HRESULT Open(
   HWND hWnd = GetActiveWindow( ),
   DBPROMPTOPTIONS dwPromptOptions = DBPROMPTOPTIONS_WIZARDSHEET 
) throw( );
HRESULT Open( 
   LPCWSTR szProgID, 
   DBPROPSET* pPropSet = NULL, 
   ULONG nPropertySets = 1 
) throw( );
HRESULT Open( 
   LPCSTR szProgID, 
   LPCTSTR pName, 
   LPCTSTR pUserName = NULL, 
   LPCTSTR pPassword = NULL, 
   long nInitMode = 0 
) throw( );

Parameters

  • clsid
    [in] The CLSID of the data provider.

  • pPropSet
    [in] A pointer to an array of DBPROPSET structures containing properties and values to be set. See Property Sets and Property Groups in the OLE DB Programmer's Reference in the Windows SDK.

  • nPropertySets
    [in] The number of DBPROPSET structures passed in the pPropSet argument.

  • pName
    [in] The name of the database to which to connect.

  • pUserName
    [in] The name of the user.

  • pPassword
    [in] The user's password.

  • nInitMode
    [in] Database initialization mode. See Initialization Propertiesin the OLE DB Programmer's Reference in the Windows SDK for a list of valid initialization modes. If nInitMode is zero, no initialization mode is included in the property set used to open the connection.

  • szProgID
    [in] A program identifier.

  • enumerator
    [in] A CEnumerator object used to obtain a moniker for opening the connection when the caller does not specify a CLSID.

  • hWnd
    [in] Handle to the window that is to be the parent of the dialog box. Using the function overload that uses the hWnd parameter will automatically invoke Service Components; see Remarks for details.

  • dwPromptOptions
    [in] Determines the style of locator dialog box to display. See Msdasc.h for possible values.

Return Value

A standard HRESULT.

Remarks

The method overload that uses the hWnd parameter opens a data source object with the service components in oledb32.dll; this DLL contains the implementation of Service Components features such as Resource Pooling, Automatic Transaction Enlistment, and so on. For more information, see "OLE DB Services" in the OLE DB Programmer's Reference at https://msdn.microsoft.com/library/default.asp?url=/library/en-us/oledb/htm/oledbole_db_services.asp?frame=true.

The method overloads that do not use the hWnd parameter open a data source object without using the service components in oledb32.dll. A CDataSource object opened with these function overloads will be unable to utilize any of the functionality of Service Components.

Example

The following code shows how to open a Jet 4.0 data source with OLE DB Templates. You treat the Jet data source as an OLE DB data source. However, your call to Open needs two property sets: one for DBPROPSET_DBINIT and the other for DBPROPSET_JETOLEDB_DBINIT, so that you can set DBPROP_JETOLEDB_DATABASEPASSWORD.

CDBPropSet rgDBPropSet[2];  // Declare two property sets;
                            // set properties elsewhere as appropriate.

hr = m_DataSource.Open(szProgId, rgDBPropSet, 2);

Requirements

Header: atldbcli.h

See Also

Concepts

CDataSource Class

CDataSource Members