• [C#]获取连接MySql数据库及常用的CRUD操作


    测试如下:

    首先添加引用:MySql.Data.dll

    链接:http://pan.baidu.com/s/1dEQgLpf 密码:bnyu

    *将链接数据库的信息放入配置文件中(app.config)

    1     <appSettings>
    2         <add key="mysql" value="server=127.0.0.1;User Id=******;password=******;Database="******"/>
    3     </appSettings>

    *在程序启动时进行启动

    1   private string mysqlString = ConfigurationManager.AppSettings["mysql"].ToString();

    ①建立mysql数据库链接

    1         //建立mysql数据库链接
    2         public MySqlConnection getMySqlConn()
    3         {
    4             //string constr = "server=localhost;User Id=root;password=123456;Database=qqmusicdistinct";
    5 string constr = mysqlString;
    6 MySqlConnection mycon = new MySqlConnection(constr); 7 return mycon; 8 }

    ②建立执行命令语句对象

    1         //建立执行命令语句对象
    2         public MySqlCommand getSqlCommand(String sql, MySqlConnection mysql)
    3         {
    4             MySqlCommand mySqlCommand = new MySqlCommand(sql, mysql);
    5             return mySqlCommand;
    6         }

    ③编写sql语句,对数据做相应处理

     1         //编写sql语句,对数据做相应处理
     2         public void setData()
     3         {
     4             MySqlConnection mysql = getMySqlConn();
     5             //查询sql
     6             String sqlSearch = "select * from student";
     7             //插入sql
     8             //String sqlInsert = "insert into student values (12,'张三',25,'大专')";
     9             //修改sql
    10             //String sqlUpdate = "update student set name='李四' where id= 3";
    11             //删除sql
    12             //String sqlDel = "delete from student where id = 12";
    13             
    14             //四种语句对象
    15             MySqlCommand mySqlCommand = getSqlCommand(sqlSearch, mysql);
    16             //MySqlCommand mySqlCommand = getSqlCommand(sqlInsert, mysql);
    17             //MySqlCommand mySqlCommand = getSqlCommand(sqlUpdate, mysql);
    18             //MySqlCommand mySqlCommand = getSqlCommand(sqlDel, mysql);
    19 
    20             mysql.Open();
    21        
    22             getResultset(mySqlCommand);
    23             //getInsert(mySqlCommand);
    24             //getUpdate(mySqlCommand);
    25             //getDel(mySqlCommand);
    26             //记得关闭
    27             mysql.Close();
    28         }

    ④Ⅰ.查询并获得结果集并遍历

     1         //查询并获得结果集并遍历
     2         public void getResultset(MySqlCommand mySqlCommand)
     3         {
     4             MySqlDataReader reader = mySqlCommand.ExecuteReader();
     5             try
     6             {
     7                 while (reader.Read())
     8                 {
     9                     if (reader.HasRows)
    10                     {
    11                         //MessageBox.Show("歌曲名:" + reader.GetString(1) + "|歌手:" + reader.GetString(2));
    12                     }
    13                 }
    14             }
    15             catch (Exception)
    16             {
    17                 MessageBox.Show("查询失败了!");
    18             }
    19             finally
    20             {
    21                 reader.Close();
    22             }
    23         }

    ④Ⅱ.添加数据

     1         //添加数据
     2         public static void getInsert(MySqlCommand mySqlCommand)
     3         {
     4             try
     5             {
     6                 mySqlCommand.ExecuteNonQuery();
     7             }
     8             catch (Exception ex)
     9             {
    10                 String message = ex.Message;
    11                 Console.WriteLine("插入数据失败了!" + message);
    12             }
    13 
    14         }

    ④Ⅲ.修改数据

     1         //修改数据
     2         public static void getUpdate(MySqlCommand mySqlCommand)
     3         {
     4             try
     5             {
     6                 mySqlCommand.ExecuteNonQuery();
     7             }
     8             catch (Exception ex)
     9             {
    10                 String message = ex.Message;
    11                 Console.WriteLine("修改数据失败了!" + message);
    12             }
    13         }

    ④Ⅳ.删除数据

     1         //删除数据
     2         public static void getDel(MySqlCommand mySqlCommand)
     3         {
     4             try
     5             {
     6                 mySqlCommand.ExecuteNonQuery();
     7             }
     8             catch (Exception ex)
     9             {
    10                 String message = ex.Message;
    11                 Console.WriteLine("删除数据失败了!" + message);
    12             }
    13         }
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  • 原文地址:https://www.cnblogs.com/ttkl/p/7730246.html
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