ADO 数据连接学习笔记

参考资料：VC知识库在线杂志：http://www.vckbase.com/vckbase/default.aspx

             CodeProject网站：http://www.codeproject.com/search.aspx?q=CListCtrlEx&sbo=kw

记录一下重点步骤：

初始化ole连接

Initializing the OLE/COM Libraries 

1 BOOL CADOMFC1App::InitInstance()
2 {
3 // Add this function to initialize the OLE/COM libraries
4     AfxOleInit();
View Code

引入ado组件

Changes to StdAfx.h 

1 #include <comdef.h>
2 
3 #import "C:\program files\common files\system\ado\msado15.dll" no_namespace \ 
4 rename( "EOF", "adoEOF" )
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申明数据连接变量

Changes to the Document Header File 

1 class CADOMFC1Doc : public CDocument
2 {
3 // Attributes
4 public:
5     BOOL m_IsConnectionOpen;
6     _ConnectionPtr m_pConnection;
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数据库连接及错误处理

OnNewDocument with Exception Handling

 1 BOOL CADOMFC1Doc::OnNewDocument() 
 2 { 
 3     if (!CDocument::OnNewDocument()) 
 4         return FALSE; 
 5 
 6     // TODO: add reinitialization code here 
 7     // (SDI documents will reuse this document) 
 8     HRESULT hr; 
 9     try 
10     { 
11         hr = m_pConnection.CreateInstance( __uuidof( Connection ) ); 
12         if (SUCCEEDED(hr)) 
13         { 
14             hr = m_pConnection->Open(_bstr_t(L"Provider=SQLOLEDB.1;Integrated Security=SSPI;Persist Security Info=False;Initial Catalog=tee;Data Source=SQL\\SQLSERVER2000"), 
15                 _bstr_t(L""), 
16                 _bstr_t(L""), 
17                 adModeUnknown);
18 
19 //获取数据连接字串可以新建一个.udl的文件，执行之后可以查看。 
20             if (SUCCEEDED(hr)) 
21             { 
22                 m_IsConnectionOpen = TRUE; 
23                 TRACE("连接成功\r\n"); 
24             } 
25         } 
26 
27     } 
28     catch (_com_error &e) 
29     { 
30         // Get info from _com_error 
31         _bstr_t bstrSource(e.Source()); 
32         _bstr_t bstrDescription(e.Description()); 
33         TRACE( "Exception thrown for classes generated by #import" ); 
34         TRACE( "\tCode = %08lx\n", e.Error()); 
35         TRACE( "\tCode meaning = %s\n", e.ErrorMessage()); 
36         TRACE( "\tSource = %s\n", (LPCTSTR) bstrSource); 
37         TRACE( "\tDescription = %s\n", (LPCTSTR) bstrDescription); 
38     } 
39     catch(...) 
40     { 
41         TRACE( "*** Unhandled Exception ***" ); 
42     }   
43 
44     return TRUE; 
45 }
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数据集获取及数据显示 

retrieve and show data

//这里用到一个类，名字为CListCtrlEx，用于列表显示数据

 1 _RecordsetPtr pRecordSet; 
 2     CADOMFC1Doc * pDoc; 
 3     pDoc = GetDocument(); 
 4     _bstr_t bstrQuery("SELECT * FROM Data"); 
 5     _variant_t vRecsAffected(0L); 
 6     try 
 7     { 
 8         pRecordSet = pDoc->m_pConnection->Execute(bstrQuery, &vRecsAffected, 
 9             adOptionUnspecified); 
10         if (!pRecordSet->GetadoEOF()) 
11         { 
12             CListCtrlEx& ctlList = (CListCtrlEx&) GetListCtrl(); 
13             ctlList.DeleteAllItems(); 
14             while(ctlList.DeleteColumn(0)); 
15             ctlList.AddColumn("  x  ",0); 
16             ctlList.AddColumn("  y  ",1); 
17             int i = 0; 
18             _variant_t vFirstName; 
19             _variant_t vLastName; 
20             while (!pRecordSet->GetadoEOF()) 
21             { 
22                 vFirstName = pRecordSet->GetCollect(L"x"); 
23                 ctlList.AddItem(i,0,(_bstr_t) vFirstName); 
24                 vLastName = pRecordSet->GetCollect(L"y"); 
25                 ctlList.AddItem(i,1,(_bstr_t) vLastName); 
26                 i++; 
27                 pRecordSet->MoveNext(); 
28             } 
29         } 
30         pRecordSet->Close(); 
31     } 
32     catch( _com_error &e ) 
33     { 
34         // Get info from _com_error 
35         _bstr_t bstrSource(e.Source()); 
36         _bstr_t bstrDescription(e.Description()); 
37         TRACE( "Exception thrown for classes generated by #import" ); 
38         TRACE( "\tCode = %08lx\n", e.Error()); 
39         TRACE( "\tCode meaning = %s\n", e.ErrorMessage()); 
40         TRACE( "\tSource = %s\n", (LPCTSTR) bstrSource); 
41         TRACE( "\tDescription = %s\n", (LPCTSTR) bstrDescription); 
42     } 
43     catch(...) 
44     { 
45         TRACE( "*** Unhandled Exception ***" ); 
46     }
View Code

断开连接

 

 1 try 
 2     { 
 3         if (m_IsConnectionOpen) 
 4         { 
 5             m_IsConnectionOpen = FALSE; 
 6             m_pConnection->Close(); 
 7             TRACE("断开成功\r\n"); 
 8         } 
 9 
10     } 
11     catch (_com_error &e) 
12     { 
13         _bstr_t bstrSource(e.Source()); 
14         _bstr_t bstrDescription(e.Description()); 
15         TRACE( "Exception thrown for classes generated by #import" ); 
16         TRACE( "\tCode = %08lx\n", e.Error()); 
17         TRACE( "\tCode meaning = %s\n", e.ErrorMessage()); 
18         TRACE( "\tSource = %s\n", (LPCTSTR) bstrSource); 
19         TRACE( "\tDescription = %s\n", (LPCTSTR) bstrDescription); 
20     } 
21     catch(...) 
22     { 
23         TRACE( "*** Unhandled Exception ***" ); 
24     }
View Code

 

 

 

 

 

 

 

posted on 2013-06-09 16:42  david_hu  阅读(215)  评论(0)    收藏  举报

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