C#对数据库的插入，删除，修改和查询

1. 插入

插入语句 string insertSte="insert into 表名 values(数据)；"；

static void Insert()

{

string connectStr = "server=127.0.0.1;port=3306;database=game3;user=root;password=123456";

MySqlConnection con = new MySqlConnection(connectStr);

//定义一个操作对象

MySqlCommand cmd = null;

try

{

con.Open();

Console.WriteLine("连接成功");

string insertStr = "insert into new_table values('13','冯总','3','2');";

cmd = new MySqlCommand(insertStr, con);

cmd.ExecuteNonQuery();//插入操作

}

catch

{

Console.WriteLine("错误");

}

finally

{

cmd.Dispose();

con.Close();

}

}

2. 删除

删除语句 string deleteStr="delete from 表名 where ××=××；"；

static void Delete()

{

string connectStr = "server=127.0.0.1;port=3306;database=game3;user=root;password=123456";

MySqlConnection con = new MySqlConnection(connectStr);

//定义一个操作对象

MySqlCommand cmd = null;

try

{

con.Open();

Console.WriteLine("连接成功");

string deleteStr = "delete from new_table where ID='13';";

cmd = new MySqlCommand(deleteStr, con);

cmd.ExecuteNonQuery();

}

catch

{

Console.WriteLine("错误");

}

finally

{

cmd.Dispose();

con.Close();

}

}

3.修改

修改语句 string updateStr="update 表名 set ××=×× where ××=××"

static void Update()

{

string connectStr = "server=127.0.0.1;port=3306;database=game3;user=root;password=123456";

MySqlConnection con = new MySqlConnection(connectStr);

//定义一个操作对象

MySqlCommand cmd = null;

try

{

con.Open();

Console.WriteLine("连接成功");

string updateStr = "update new_table set ID=14,time=5 where age=3;";

cmd = new MySqlCommand(updateStr, con);

cmd.ExecuteNonQuery();

}

catch

{

Console.WriteLine("错误");

}

finally

{

cmd.Dispose();

con.Close();

}

}

4.查询

查询语句 string querStr="select ×× ×× ×× ×× from 表名;";

static void Read()

{

string connectStr = "server=127.0.0.1;port=3306;database=game3;user=root;password=123456";

MySqlConnection con = new MySqlConnection(connectStr);

//定义一个操作对象

MySqlCommand cmd = null;

try

{

con.Open();

Console.WriteLine("连接成功");

string queryStr = "select ID,name,age,time from new_table;";//111111111111111111111111111111111

cmd = new MySqlCommand(queryStr, con);

MySqlDataReader re = cmd.ExecuteReader();//读取操作DataReader,主要用于读取表中的查询结果，并且是以只读方式读取的,ExecuteReader尽可能快地对数据库进行查询并得到结果

while (re.Read())

{

Console.WriteLine(re[0].ToString() + " " + re[1].ToString() + " " + re[2].ToString() + " " + re[3].ToString());

}

}

catch

{

Console.WriteLine("错误");

}

finally

{

cmd.Dispose();

con.Close();

}

}