C#實作連接配接資料庫

C#實作連接配接資料庫

一、Oracle

查詢

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 連結
            string s = "Data Source=(DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = ip位址 )(PORT =端口)))(CONNECT_DATA = (SID=SID号)(SERVER = DEDICATED)));uid = 使用者名; password=密碼;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
  (欄位1, 欄位2, 欄位3,....)
VALUES
  (欄位1值, 欄位2值, 欄位3值, ....)
";

                OracleCommand oaCmd = new OracleCommand(sql, oc);
                //oaCmd.Parameters.Add("參數", OracleType.VarChar, 30).Value = "";
                oaCmd.CommandType = CommandType.Text;
                oaCmd.ExecuteNonQuery();
                oc.Close();

            }
        }
        catch (Exception ex)
        {
           
        }
    }      

二、SQLServer

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;
    }      

public static void DoInser(string login_user, string login_db)
    {
        try
        {

            string s = "資料庫連結";
            using (SqlConnection sqlConnection = new SqlConnection(s))
            {
                sqlConnection.Open();
                string sql = @" INSERT INTO 表名
  (欄位1, 欄位2, 欄位3,....)
VALUES
  (欄位1值, 欄位2值, 欄位3值, ....)
";

                SqlDataAdapter sqlDa = new SqlDataAdapter(sql, sqlConnection);
                sqlDa.InsertCommand.Parameters.Add("參數", SqlDbType.VarChar, 30).Value = "";

                SqlCommand cmd = new SqlCommand();
                cmd.CommandType = CommandType.Text;
                cmd.ExecuteNonQuery();

                sqlConnection.Close();

            }
        }
        catch (Exception ex)
        {
           
        }
    }      

工具類

public DataTable ExecuteQuery(string sqlStr)      //用于查詢；其實是相當于提供一個可以傳參的函數，到時候寫一個sql語句，存在string裡，傳給這個函數，就會自動執行。
    {
        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;
    }      

本文來自部落格園，作者：農碼一生，轉載請注明原文連結：https://www.cnblogs.com/wml-it/p/15148239.html

技術的發展日新月異，随着時間推移，無法保證本部落格所有内容的正确性。如有誤導，請大家見諒，歡迎評論區指正！ 個人開源代碼連結: GitHub:

https://github.com/ITMingliang

Gitee:

https://gitee.com/mingliang_it

GitLab:

https://gitlab.com/ITMingliang

進開發學習交流群：