C#连接MySQL数据库（增删改查）

using System;
using MySql.Data.MySqlClient;

namespace CSharp直接连接MySQL
{
    class Program
    {
        static void Main(string[] args)
        {
            //Read();
            //Insert();
            //Update();
            //Delete();
            //ExcuteSccalar();//查询一个值更方便
            Console.WriteLine(VerifyUser("w", "2"));//验证库中是否有此数据
            Console.ReadKey();
        }
        static bool VerifyUser(string username, string password)
        {
            string connectStr = "server=127.0.0.1;port=3306;database=zxw;user=root;password=123456";//本机配置
            MySqlConnection conn = new MySqlConnection(connectStr);
            try
            {
                conn.Open();//开启数据库
                Console.WriteLine("已连接。。");
                //string sql = "select * from users where username='" + username + "' and password='" + password + "'";//按照自定义查询规则组拼sql
                string sql = "select * from users where username=@username and password=@password";//按照自定义查询规则组拼sql @符号等于临时定义一个数据
                MySqlCommand cmd = new MySqlCommand(sql, conn);
                cmd.Parameters.AddWithValue("username", username);//给sql语句中的@定义赋值
                cmd.Parameters.AddWithValue("password", password);//给sql语句中的@定义赋值
                MySqlDataReader reader = cmd.ExecuteReader();//查询
                if (reader.Read()) return true;
                else return false;
            }
            catch (Exception e)
            {
                Console.WriteLine(e.ToString());
            }
            conn.Close();//关闭连接
            return false;
        }
        static void Read()
        {
            string connectStr = "server=127.0.0.1;port=3306;database=zxw;user=root;password=123456";//本机配置
            MySqlConnection conn = new MySqlConnection(connectStr);
            try
            {
                conn.Open();//开启数据库
                Console.WriteLine("已连接。。");
                string sql = "select * from users";
                MySqlCommand cmd = new MySqlCommand(sql, conn);
                MySqlDataReader reader = cmd.ExecuteReader();//查询
                while (reader.Read())//Read（）返回值bool
                {
                    //Console.WriteLine(reader[0].ToString() + "  " + reader[1].ToString() + "  " + reader[2].ToString());//通过read数组取值
                    //Console.WriteLine(reader.GetString(0) + "  " + reader.GetString(1) + "  " + reader.GetInt16(2));//通过get方法读取
                    Console.WriteLine(reader.GetString("username") + "  " + reader.GetString("password") + "  " + reader.GetInt16("id"));//通过列名索引读取
                }

            }
            catch (Exception e)
            {
                Console.WriteLine(e.ToString());
            }
            conn.Close();//关闭连接
            Console.ReadKey();
        }
        static void Insert()
        {
            string connectStr = "server=127.0.0.1;port=3306;database=zxw;user=root;password=123456";//本机配置
            MySqlConnection conn = new MySqlConnection(connectStr);
            try
            {
                conn.Open();//开启数据库
                Console.WriteLine("已连接。。");
                string sql = "insert into users(username,password) values('" + DateTime.Now + "','zxw')";//当前时间
                MySqlCommand cmd = new MySqlCommand(sql, conn);
                int result = cmd.ExecuteNonQuery();//返回值受数据库中数据的行数影响
                Console.WriteLine("插入完成");
            }
            catch (Exception e)
            {
                Console.WriteLine(e.ToString());
            }
            conn.Close();//关闭连接
            Console.ReadKey();
        }
        static void Update()
        {
            string connectStr = "server=127.0.0.1;port=3306;database=zxw;user=root;password=123456";//本机配置
            MySqlConnection conn = new MySqlConnection(connectStr);
            try
            {
                conn.Open();//开启数据库
                Console.WriteLine("已连接。。");
                string sql = "update users set username='oo',password='oo' where id=1";
                MySqlCommand cmd = new MySqlCommand(sql, conn);
                int result = cmd.ExecuteNonQuery();//返回值受数据库中数据的行数影响
                Console.WriteLine("更新完成");
            }
            catch (Exception e)
            {
                Console.WriteLine(e.ToString());
            }
            conn.Close();//关闭连接
            Console.ReadKey();
        }
        static void Delete()
        {
            string connectStr = "server=127.0.0.1;port=3306;database=zxw;user=root;password=123456";//本机配置
            MySqlConnection conn = new MySqlConnection(connectStr);
            try
            {
                conn.Open();//开启数据库
                Console.WriteLine("已连接。。");
                string sql = "delete from users where id=1";
                MySqlCommand cmd = new MySqlCommand(sql, conn);
                int result = cmd.ExecuteNonQuery();//返回值受数据库中数据的行数影响
                Console.WriteLine("删除完成");
            }
            catch (Exception e)
            {
                Console.WriteLine(e.ToString());
            }
            conn.Close();//关闭连接
            Console.ReadKey();
        }
        static void ExcuteSccalar()
        {
            string connectStr = "server=127.0.0.1;port=3306;database=zxw;user=root;password=123456";//本机配置
            MySqlConnection conn = new MySqlConnection(connectStr);
            try
            {
                conn.Open();//开启数据库
                Console.WriteLine("已连接。。");
                string sql = "select count(*) from users";
                MySqlCommand cmd = new MySqlCommand(sql, conn);
                object o = cmd.ExecuteScalar();//返回值即为查询结果
                int count = Convert.ToInt32(o.ToString());
                Console.WriteLine(count);
            }
            catch (Exception e)
            {
                Console.WriteLine(e.ToString());
            }
            conn.Close();//关闭连接
            Console.ReadKey();
        }
    }
}