ADO调用，高分赠送，急，在线等

Paris_Luo 2002-12-06 08:05:41

_ConnectionPtr m_pCon;
if(FAILED(hr=m_pCon->Open(_bstrDataSource,
_bstr_t(L""),
_bstr_t(L""),
adModeUnknown)))
return hr;
谁能解释一下，open函数中4个参数的含义？为什么msdn中差不到ado调用方法？
我想调一个interbase的数据库，有用户和密码，应该在什么地方更改，是否有特别的地方？

...全文

60 7 打赏收藏转发到动态举报

写回复

用AI写文章

7 条回复

切换为时间正序

请发表友善的回复…

发表回复

fingerfox 2002-12-07

打赏
举报

Open Method (ADO Connection)
Opens a connection to a data source.

Syntax
connection.Open ConnectionString, UserID, Password, Options
Parameters
ConnectionString
Optional. A String value that contains connection information. See the ConnectionString property for details on valid settings.
UserID
Optional. A String value that contains a user name to use when establishing the connection.
Password
Optional. A String value that contains a password to use when establishing the connection.
Options
Optional. A ConnectOptionEnum value that determines whether this method should return after (synchronously) or before (asynchronously) the connection is established.
Remarks
Using the Open method on a Connection object establishes the physical connection to a data source. After this method successfully completes, the connection is live and you can issue commands against it and process the results.

Use the optional ConnectionString argument to specify either a connection string containing a series of argument = value statements separated by semicolons, or a file or directory resource identified with a URL. The ConnectionString property automatically inherits the value used for the ConnectionString argument. Therefore, you can either set the ConnectionString property of the Connection object before opening it, or use the ConnectionString argument to set or override the current connection parameters during the Open method call.

If you pass user and password information both in the ConnectionString argument and in the optional UserID and Password arguments, the UserID and Password arguments will override the values specified in ConnectionString.

When you have concluded your operations over an open Connection, use the Close method to free any associated system resources. Closing an object does not remove it from memory; you can change its property settings and use the Open method to open it again later. To completely eliminate an object from memory, set the object variable to Nothing.

Remote Data Service Usage When used on a client-side Connection object, the Open method doesn't actually establish a connection to the server until a Recordset is opened on the Connection object.
Note URLs using the http scheme will automatically invoke the Microsoft OLE DB Provider for Internet Publishing. For more information, see Absolute and Relative URLs.
See Also
Visual Basic Example | VBScript Example | Visual C++ Example | Visual J++ Example

Open Method (ADO Record) | Open Method (ADO Recordset) | Open Method (ADO Stream) | OpenSchema Method

Applies To: Connection Object

xsc2001 2002-12-07

打赏
举报

_ConnectionPtr pConn;
if (FAILED(pConn.CreateInstance("ADODB.Connection")))
{
AfxMessageBox("Create Instance failed!");
return;
}

CString strSRC;

strSRC="DRIVER=Microsoft Visual FoxPro Driver;";//这里可写你所选择的数据库驱动类型
strSRC+="SourceType=DBF;";
strSRC+="SourceDB=";
strSRC+=strFoldName;//在这里写你的数据库表存放的路径
strSRC+=";UID=SA;PWD=";
_variant_t varSRC(strSRC);

_bstr_t bstrSRC(strSRC);

if (FAILED(pConn->Open(bstrSRC,"","",-1)))
{
AfxMessageBox("Can not open Database!");
pConn.Release();
return;
}

xsc2001 2002-12-07

打赏
举报

_ConnectionPtr pConn;
if (FAILED(pConn.CreateInstance("ADODB.Connection")))
{
AfxMessageBox("Create Instance failed!");
return;
}

_bstr_t bstrSRC(strSRC);

if (FAILED(pConn->Open(bstrSRC,"","",-1)))
{
AfxMessageBox("Can not open Database!");
pConn.Release();
return;
}

xlwz 2002-12-07