C#winform建立一个共用的数据库连接-技术开发专区

C#winform建立一个共用的数据库连接

作者：CSDN　编辑：胡铭娅 2009-02-11 17:34 来源：IT168�

【IT168 技术文档】

using   System;
  using   System.Xml;
  using   System.Data.OleDb;
  using   System.Data;

  namespace   ACS
  {
  ///   <summary>
  ///   對數據庫進行更新
  ///   </summary>
  ///   AIDU數據庫連接
  ///   Retrieval   返回查詢Dataset
  ///   Translation與數據庫進行交易[Access   =   true][fail   =   false]
  ///

  public   class   AIDU
  {

  #region   連接失敗返回失敗消息--[Link   Ok   return   null][Link   fail   return   ErrorMessage]
  public   string   ErrorMsg()
  {
  return   sErrorMsg;
  }

  #endregion

  #region   設置公共連接對像字串--[   sAcsCon   ]
  public   string   sAcsConString()
  {
  string   sConString   =   "Provider=Microsoft.Jet.OLEDB.4.0;Data   Source   ="+@"KSZH.mdb";
  // string   sConString   =   "Provider=OraOLEDB.Oracle.1;Password=mes_ks1;Persist   Security   Info=True;User   ID=mes_ks1;Data   Source=linux;Extended   Properties=";
  return   sConString;
  }


  public   string   sAcsCon
  {
  get{return   sAcsConString();}
  }

  #endregion

  #region   設置公共連接對像--[   Link_cn   ]

  public   OleDbConnection   Link_cn
  {
  get{return   Acs_cn();}
  }

  public   OleDbConnection   Acs_cn()
  {
  OleDbConnection   cn   =   new   OleDbConnection(sAcsCon);
  if(cn.State   ==   ConnectionState.Closed)
  {
  cn.Open();
  }
  return   cn;
  }

  #endregion

  //連接失敗後的返回消息
  private   string   sErrorMsg   =""   ;
  //連接標志變量   [bFlag   =   true   Connection   Database   Success]
  //[bFlag   =   false   Connection   Database   unSuccess]
  private   bool   bFlag   =   false;

  #region   數據庫連接--[   LINK-TEST   ]

  public   bool   AIDU_Link()
  {
  OleDbConnection   TestCn   =   new   OleDbConnection(sAcsCon);
  //測試數據庫連接
  try
  {
  if(TestCn.State   !=   ConnectionState.Open)
  {
  TestCn.Open();
  bFlag   =   true;
                                  }
  }
  catch(Exception   e)
  {
  sErrorMsg   =   e.Message;
  }
  finally
  {
  if(TestCn.State   ==   ConnectionState.Open)
  {
  TestCn.Close();
  }
  }
  return   bFlag;
  }

  #endregion

  #region   資料查詢--[   SELECT   ]
  public   DataSet   Select(string   sCmdString)
  {
  //建立CONNECTION對像
  OleDbConnection   cn1=new   OleDbConnection(sAcsCon);
  //建立DATASET對像,做資料返回值
  DataSet   oDs   =   new   DataSet();
  try
  {//建立Adapter對像
  OleDbDataAdapter   myAdapter   =   new   OleDbDataAdapter(sCmdString,cn1);
  myAdapter.Fill(oDs);
  }
  catch
  {
  cn1.Close();
  }

  return   oDs;
  }
  #endregion

  #region   數據資料更新--[   Update   ]

  //執行--[   UPDATE   ][   INSERT   ][   DELETE   ]
  //[   The   command   Execute   sccess   return   1]
  //[   The   command   Execute   unSuccess   return   -1]
  public   int   UpdateCmd(string   CommandString)
  {
  int   nResult   =   -1;
  //進行一個本地交易
  // OleDbTransaction   myTran   =   Link_cn.BeginTransaction(IsolationLevel.ReadCommitted);
  // myTran.Begin();
  //oledbcommand   命令執行交易
  OleDbCommand   myCmd   =   new   OleDbCommand(CommandString,Link_cn);

  //和數據庫進這行數據交易
  try
  {
  //提交數據
  myCmd.ExecuteNonQuery();
  // myTran.Commit();
  nResult   =   1;
  }
  catch(OleDbException   oe)
  {
  //出錯數據回滾原來的狀態，保持數據庫一致性
  // myTran.Rollback();
  nResult   =   -1;
  throw   oe;
  }
  finally
  {
  //執行交易後關閉聯接
  Link_cn.Close();
  }
  return   nResult;
  }
  #endregion
  }


  #region   處理字符,以符合SQL語句用--[   class   sTringAdd   ]
  public   class   sTringAdd
  {

  public   sTringAdd(){}

  public   string   SQLQ(string   sText)
  {
  sText   =   "'"+sText+"'";
  return   sText;
  }

  public   string   SQLQ(int   n)
  {
  return   n.ToString();
  }

  public   string   SQLQ(double   n)
  {
  return   n.ToString();
  }

  public   string   SQLQC(string   sText)
  {
  sText   =   "'"+sText+"',";
  return   sText;
  }

  public   string   SQLQC(int   nText)
  {
                          string   sText   =   nText.ToString()+",";
  return   sText;
  }

  public   string   SQLQC(double   nText)
  {
  string   sText   =   nText.ToString()+",";
  return   sText;
  }
  }
  #endregion

  }

关注我们