学习mysql

 1 using System;
 2 using System.Collections.Generic;
 3 using System.Linq;
 4 using System.Text;
 5 using System.Threading.Tasks;
 6 using MySql.Data.MySqlClient;
 7 
 8 namespace Read
 9 {
10     class Program
11     {
12         static void Main(string[] args)
13         {
14             string connStr = "Database=test;Data Source=127.0.0.1;port=3306;User Id=root;Password=user";
15             MySqlConnection cnn = new MySqlConnection(connStr);//创建连接通道
16 
17             cnn.Open();//打开
18 
19             //Select(cnn);//查
20             //Insert(cnn);//增
21             //Delete(cnn);//删
22             Update(cnn);//改
23             Select(cnn);
24 
25             cnn.Close();
26 
27         }
28         static void Update(MySqlConnection cnn)
29         {
30             MySqlCommand cmd = new MySqlCommand("update user set passworld=@pwd where id=18",cnn);
31             cmd.Parameters.AddWithValue("pwd", "aaaaaa");
32             cmd.ExecuteNonQuery();
33         }
34         static void Delete(MySqlConnection cnn)
35         {
36             MySqlCommand cmd = new MySqlCommand("delete from user where id=@id",cnn);
37 
38             cmd.Parameters.AddWithValue("id", 17);
39 
40             cmd.ExecuteNonQuery();
41         }
42         static void Insert(MySqlConnection cnn)//插入
43         {
44             string username = "zhangsan";
45             string passworld = "zhangsan‘;delete from user;";
46             //Console.WriteLine("insert into user set username= ‘" + username + "‘" + ",passworld=‘" + passworld + "‘");
47             //MySqlCommand cmd = new MySqlCommand("insert into user set username= ‘"+username+"‘"+",passworld=‘"+passworld+"‘",cnn);
48             MySqlCommand cmd = new MySqlCommand("insert into user set username=@id,passworld=@pwd", cnn);
49 
50             cmd.Parameters.AddWithValue("id", username);
51             cmd.Parameters.AddWithValue("pwd", passworld);
52 
53             cmd.ExecuteNonQuery();
54            
55         }
56         static void Select(MySqlConnection cnn)
57         {
58             MySqlCommand cmd = new MySqlCommand("select * from user ", cnn);//使用SQL命令查询ID
59 
60             MySqlDataReader reader = cmd.ExecuteReader();//执行命令
61             while (reader.Read())
62             {
63                 string username = reader.GetString("username");
64                 string passworld = reader.GetString("passworld");
65                 Console.WriteLine(username + "+" + passworld);
66             }
67             reader.Close();
68         }
69     }
70 }