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一、Oracle查询public static DataTable QueryData(){ DataTable dtResult=new DataTable(); try { using (OracleConnection oc=new OracleConnection(HttpContext.Current.Session[DBName].ToString().Trim())) { oc.Open(); string sql=@; } } catch (Exception ex) { // 异常处理 } return dtResult;}

一、Oracle

查询

public static DataTable QueryData() { DataTable dtResult = new DataTable(); try { using (OracleConnection oc = new OracleConnection(HttpContext.Current.Session["DBName"].ToString().Trim())) { oc.Open(); string sql = @" SELECT * FROM DUAL"; OracleDataAdapter oaCmd = new OracleDataAdapter(sql, oc); //oaCmd.SelectCommand.Parameters.Add("fDate", OracleType.VarChar, 50).Value = DateTime.Now.ToString("yyyy/MM/dd") + " " + "00:00:00"; //oaCmd.SelectCommand.Parameters.Add("eDate", OracleType.VarChar, 50).Value = DateTime.Now.ToString("yyyy/MM/dd") + " " + "23:59:59"; oaCmd.Fill(dtResult); oc.Close(); } } catch (Exception ex) { } return dtResult; }

更新

public static void DoInser(string login_user, string login_db) { try { //string strDBXMLFile = HttpContext.Current.Server.MapPath(HttpContext.Current.Request.ApplicationPath.ToString()) + @"\DB.XML"; //DataSet dsXML = new DataSet(); //dsXML.ReadXml(strDBXMLFile); //DataTable dtAEPDB = dsXML.Tables["DB_NAME"]; //DB 链接 string s = "Data Source=(DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = ip地址 )(PORT =端口)))(CONNECT_DATA = (SID=SID号)(SERVER = DEDICATED)));uid = 用户名; password=密码;Connection Lifetime=60;Max Pool Size=50;Min Pool Size=0;Pooling=true"; using (OracleConnection oc = new OracleConnection(s)) { oc.Open(); string sql = @" INSERT INTO 表名 (栏位1, 栏位2, 栏位3,....) VALUES (栏位1值, 栏位2值, 栏位3值, ....)"; OracleCommand oaCmd = new OracleCommand(sql, oc); //oaCmd.Parameters.Add("参数", OracleType.VarChar, 30).Value = ""; oaCmd.CommandType = CommandType.Text; oaCmd.ExecuteNonQuery(); oc.Close(); } } catch (Exception ex) { } }

二、SQLServer

查询

public static DataTable QueryData() { DataTable dtResult = new DataTable(); try { using (SqlConnection sqlConnection = new SqlConnection(HttpContext.Current.Session["DBName"].ToString().Trim())) { sqlConnection.Open(); string sql = @" SELECT * FROM DUAL"; SqlDataAdapter sqlDa = new SqlDataAdapter(sql, sqlConnection); sqlDa.SelectCommand.Parameters.Add("fDate", SqlDbType.VarChar, 50).Value = DateTime.Now.ToString("yyyy/MM/dd") + " " + "00:00:00"; sqlDa.SelectCommand.Parameters.Add("eDate", SqlDbType.VarChar, 50).Value = DateTime.Now.ToString("yyyy/MM/dd") + " " + "23:59:59"; sqlDa.Fill(dtResult); sqlConnection.Close(); } } catch (Exception ex) { } return dtResult; }

更新

public static void DoInser(string login_user, string login_db) { try { string s = "数据库链接"; using (SqlConnection sqlConnection = new SqlConnection(s)) { sqlConnection.Open(); string sql = @" INSERT INTO 表名 (栏位1, 栏位2, 栏位3,....) VALUES (栏位1值, 栏位2值, 栏位3值, ....)"; SqlDataAdapter sqlDa = new SqlDataAdapter(sql, sqlConnection); sqlDa.InsertCommand.Parameters.Add("参数", SqlDbType.VarChar, 30).Value = ""; SqlCommand cmd = new SqlCommand(); cmd.CommandType = CommandType.Text; cmd.ExecuteNonQuery(); sqlConnection.Close(); } } catch (Exception ex) { } }

工具类

public DataTable ExecuteQuery(string sqlStr) //用于查询；其实是相当于提供一个可以传参的函数，到时候写一个sql语句，存在string里，传给这个函数，就会自动执行。 { SqlConnection con = new SqlConnection("MySqlCon"); con.Open(); SqlCommand cmd = new SqlCommand(); cmd.Connection = con; cmd.CommandType = CommandType.Text; cmd.CommandText = sqlStr; DataTable dt = new DataTable(); SqlDataAdapter msda; msda = new SqlDataAdapter(cmd); msda.Fill(dt); con.Close(); return dt; } public int ExecuteUpdate(string sqlStr) //用于增删改; { SqlConnection con = new SqlConnection("MySqlCon"); con.Open(); SqlCommand cmd = new SqlCommand(); cmd.Connection = con; cmd.CommandType = CommandType.Text; cmd.CommandText = sqlStr; int iud = 0; iud = cmd.ExecuteNonQuery(); con.Close(); return iud; }

到此这篇关于C#连接数据库的文章就介绍到这了。希望对大家的学习有所帮助，也希望大家多多支持自由互联。