NuGet:
- Dapper 2.0.35
- MySql.Data
- System.Data
实体(Entity)
1 public class student 2 { 3 public int Id { get; set; } 4 public string RealName { get; set; } 5 public DateTime EnrollmenDate { get; set; } 6 }
配置文件数据库连接
<connectionStrings> <add name="mysqlConn" connectionString="server=127.0.0.1;database=数据库;User ID=root;password=密码"/> </connectionStrings>
MySql连接字符串
1 private static string connStr = string.Empty; 2 public MySqlOperation() 3 { 4 connStr = System.Configuration.ConfigurationManager.ConnectionStrings["mysqlConn"].ConnectionString; 5 }
查询语句
1 /// <summary> 2 /// 查询所有 3 /// </summary> 4 /// <returns>lists</returns> 5 public List<student> Query() 6 { 7 if (string.IsNullOrEmpty(connStr)) 8 { 9 return new List<student>(); ; 10 } 11 try 12 { 13 using (IDbConnection db = new MySqlConnection(connStr)) 14 { 15 db.Open();//打开数据库 16 string mysqlStr = "select * from student"; 17 List<student> lists = db.Query<student>(mysqlStr).ToList(); 18 db.Close();//关闭数据库 19 return lists; 20 } 21 } 22 catch (Exception) 23 { 24 return new List<student>(); 25 } 26 } 27 /// <summary> 28 /// 根据Id查询 29 /// </summary> 30 /// <param name="id"></param> 31 /// <returns>lists</returns> 32 public List<student> Query(string id) 33 { 34 if (string.IsNullOrEmpty(connStr)) 35 { 36 return new List<student>(); 37 } 38 try 39 { 40 using (IDbConnection db = new MySqlConnection(connStr)) 41 { 42 db.Open();//打开数据库 43 string mysqlStr = "select * from student where Id=@id"; 44 List<student> lists = db.Query<student>(mysqlStr, new { Id = id }).ToList(); 45 db.Close();//关闭数据库 46 return lists; 47 } 48 } 49 catch (Exception) 50 { 51 return new List<student>(); 52 } 53 }
插入语句
1 /// <summary> 2 /// 插入数据 3 /// </summary> 4 /// <param name="student">student</param> 5 /// <returns>-1:连接字符串为空,-2:新增失败</returns> 6 public int Insert(student student) 7 { 8 if (string.IsNullOrEmpty(connStr)) 9 { 10 return -1; 11 } 12 try 13 { 14 using (IDbConnection db = new MySqlConnection(connStr)) 15 { 16 db.Open();//打开数据库 17 string mysqlStr = "insert into student(Id,RealName,EnrollmenDate) values(@Id,@RealName,@EnrollmenDate)"; 18 int list = db.Execute(mysqlStr, student); 19 db.Close();//关闭数据库 20 return list; 21 } 22 } 23 catch (Exception) 24 { 25 return -2; 26 } 27 }
删除数据
1 /// <summary> 2 /// 删除数据 3 /// </summary> 4 /// <param name="id"></param> 5 /// <returns></returns> 6 public int Delect(string id) 7 { 8 if (string.IsNullOrEmpty(connStr)) 9 { 10 return -1; 11 } 12 try 13 { 14 using (IDbConnection db = new MySqlConnection(connStr)) 15 { 16 db.Open();//打开数据库 17 string mysqlStr = "delete from student where Id=@id"; 18 int list = db.Execute(mysqlStr, new { Id = id }); 19 db.Close();//关闭数据库 20 return list; 21 } 22 } 23 catch (Exception) 24 { 25 return -2; 26 } 27 }
更新数据
1 /// <summary> 2 /// 更新信息 3 /// </summary> 4 /// <param name="student"></param> 5 /// <returns>-1:连接字符串为空,-2:更新失败</returns> 6 public int Update(student student) 7 { 8 if (string.IsNullOrEmpty(connStr)) 9 { 10 return -1; 11 } 12 try 13 { 14 using (IDbConnection db = new MySqlConnection(connStr)) 15 { 16 db.Open();//打开数据库 17 string mysqlStr = "update student set RealName=@RealName where Id=@Id"; 18 int list = db.Execute(mysqlStr, student); 19 db.Close();//关闭数据库 20 return list; 21 } 22 } 23 catch (Exception) 24 { 25 return -2; 26 } 27 }