C#从数据库mysql读取数据

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using MySql.Data.MySqlClient;
namespace 电子商务
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        private void Form1_Load(object sender, EventArgs e)
        {
        }
        private void button1_Click(object sender, EventArgs e)
        {
            string str = "Host=localhost;User ID=root;Password=;Port = 3306;DataBase=animals;Charset=utf8;";
            MySqlConnection conn = new MySqlConnection(str);
            conn.Open();//
                        ////拿到数据库并打开连接
                        //string sql = "select *from student";
                        //MySqlCommand cmd = new MySqlCommand(sql, conn);
                        //MySqlDataAdapter mda = new MySqlDataAdapter(cmd);
                        //DataSet ds = new DataSet();
                        //mda.Fill(ds);
                        //dataGridView1.DataSource = ds.Tables[0];
                        ////MySqlDataReader dr = cmd.ExecuteReader();
                        //conn.Close();
            /*1.访问数据库的五大步骤
              2.拿到要发送的sql语句
              3.执行 sql 语句
              4.拿到执行后的聚过
              5.关闭连接 切记关闭连接
            */
            ////1 拿到数据库的连接 并打开连接
            //string url = "User ID=root;Password=;Host=localhost;Port=3306;Database=xx;charset=xx;";
            //MySqlConnection con = new MySqlConnection(url);
            //con.Open();
            ////2.要拿到要发送的sql语句
            //string sql = "select id from student where name=‘kobe‘";
            //MySqlCommand com = new MySqlCommand(sql, con);
            //// 3 执行 sql 语句
            //MySqlDataReader reader = com.ExecuteReader();
            //reader.Read();// Read() 每次调用 都会从结果集中返回一行数据
            //reader.GetInt32(0);
            /*1.访问数据库的五大步骤
              2.拿到要发送的sql语句
              3.执行 sql 语句
              4.拿到执行后的聚过
              5.关闭连接 切记关闭连接
            */
            //1 拿到数据库的连接 并打开连接
            string url = "User ID=root;Password=;Host=localhost;Port=3306;Database=students;";
            MySqlConnection con = new MySqlConnection(url);
            con.Open();
            //2.要拿到要发送的sql语句
            string sql = "select *from student where name=‘kobe‘";
            MySqlCommand com = new MySqlCommand(sql, con);
            // 3 执行 sql 语句
            MySqlDataReader reader = com.ExecuteReader();
            reader.Read();// Read() 每次调用 都会从结果集中返回一行数据
            //reader.GetInt32(0);
            Console.WriteLine(reader.GetInt32(0));
            con.Close();
            ////对数据库进行  增  删  改  查
            ////1 拿到数据库的连接 并打开连接
            //string url = "User ID=root;Password=root;Host=localhost;Port=3306;Database=students;";
            //MySqlConnection con = new MySqlConnection(url);
            //con.Open();
            //string sql = "insert into student values(11,‘hahahaha‘,‘man‘,6)";//添加信息
            //MySqlCommand cmd = new MySqlCommand(sql, con);
            //int result = cmd.ExecuteNonQuery();
            //Console.WriteLine("数据库打开结果："+result);
            //con.Close();
            //FindStudent("kobe");
        }
        public static bool FindStudent(string name)
        {
            bool b = false;
            string url = "User ID=root;Password=root;Host=localhost;Port=3306;Database=students;";
            MySqlConnection con = new MySqlConnection(url);
            con.Open();
            string sql = "select *from studnet where name=‘{0}‘ ";
            sql = string.Format(sql, name);
            // Console.WriteLine(sql);
            MySqlCommand cmd = new MySqlCommand(sql, con);
            MySqlDataReader reader = cmd.ExecuteReader();
            b = reader.Read();
            return b;
        }
    }
}

原文地址：https://www.cnblogs.com/sq45711478/p/9481087.html