ADO实例

  1 //rename作用：解决EOF重定义问题，dll中定义的EOF和程序定义的EOF冲突
  2 /*no_namespace作用：
  3 #import msado15.dll 生成文件 msado15.tlh，默认是有namespace ADODB {}，
  4 所有内容都包在这个名字空间中，访问时需要输入命名空间；
  5 用了no_namespace 生成的头文件中没有namespace，所有内容是全局的，方便访问。
  6 也可以使用 using namespace ADODB。
  7 */
  8 #import "C:\\Program Files\\Common Files\\System\\ado\\msado15.dll" rename("EOF", "adoEOF") no_namespace
  9 //using namespace ADODB;
 10
 11 /*CONNSTRING生成过程：
 12 新建一个记事本文件，后缀改为udl，然后双击打开，配置好后用记事本打开，即可得到CONNSTRING
 13 */
 14 #define CONNSTRING "Provider=SQLOLEDB.1;Integrated Security=SSPI;Persist Security Info=False;Initial Catalog=test;Data Source=."
 15
 16
 17 void CMy2014_09_11Dlg::OnBtnSelect()
 18 {
 19     //清空listview
 20     m_ctrlResult.DeleteAllItems();
 21
 22     //COM初始化
 23     CoInitialize(NULL);
 24
 25     //定义连接对象的智能指针
 26     _ConnectionPtr conn;
 27     //定义记录集对象的智能指针
 28     _RecordsetPtr  rs;
 29
 30     try
 31     {
 32         HRESULT hr;
 33
 34         //创建连接对象（智能指针初始化，. 表示调用智能指针的成员函数）
 35         //{00000514-0000-0010-8000-00AA006D2EA4}
 36         hr = conn.CreateInstance("ADODB.Connection");
 37
 38         //连接数据库（-> 表示调用智能指针指向对象的成员函数，即调用连接对象的成员函数）
 39         hr = conn->Open(CONNSTRING, "", "", adConnectUnspecified);
 40
 41         //构造查询语句
 42         UpdateData(TRUE);
 43         CString strSQL = "select * from t_student where 1 = 1";
 44         if (m_strSno.Compare("*") != 0)
 45         {
 46             CString strChild = " and sno = ‘"+ m_strSno +"‘";
 47             strSQL += strChild;
 48         }
 49         if (m_strSname.Compare("*") != 0)
 50         {
 51             CString strChild = " and sname = ‘"+ m_strSname +"‘";
 52             strSQL += strChild;
 53         }
 54         if (m_strSex.Compare("*") != 0)
 55         {
 56             CString strChild = " and sex = ‘"+ m_strSex +"‘";
 57             strSQL += strChild;
 58         }
 59         if (m_strBirthday.Compare("*") != 0)
 60         {
 61             CString strChild = " and birthday = ‘"+ m_strBirthday +"‘";
 62             strSQL += strChild;
 63         }
 64
 65         //执行命令
 66         rs = conn->Execute(strSQL.GetBuffer(0), NULL, adOptionUnspecified);
 67
 68         //获取字段数量
 69         int nCount = rs->Fields->GetCount();
 70
 71         //获取并输出数据
 72         HWND hList = m_ctrlResult.GetSafeHwnd();
 73         LVITEM lvi = {0};
 74         lvi.mask = LVIF_TEXT;
 75         while(!rs->adoEOF)
 76         {
 77             int nIndex = 0;
 78             for (int i = 0; i < nCount; i++)
 79             {
 80                 if (i == 0)
 81                 {
 82                     lvi.iItem = nIndex;
 83                     //发送LVM_INSERTITEM消息时，subitem必须为0
 84                     lvi.iSubItem = i;
 85                     CString strTmp = (char*)(_bstr_t)rs->Fields->Item[(long)i]->Value;
 86                     lvi.pszText = strTmp.GetBuffer(0);
 87                     //返回值为item的索引
 88                     nIndex = ::SendMessage(hList, LVM_INSERTITEM, 0, (LPARAM)&lvi);
 89                 }
 90                 else
 91                 {
 92                     lvi.iItem = nIndex;
 93                     lvi.iSubItem = i;
 94                     CString strTmp = (char*)(_bstr_t)rs->Fields->Item[(long)i]->Value;
 95                     lvi.pszText = strTmp.GetBuffer(0);
 96                     ::SendMessage(hList, LVM_SETITEM, 0, (LPARAM)&lvi);
 97                 }
 98             }
 99
100             rs->MoveNext();
101         }
102
103     }
104     catch (_com_error e)
105     {
106         MessageBox(e.Description());
107     }
108
109     //关闭连接
110     conn->Close();
111
112     //COM反初始化
113     CoUninitialize();
114 }