ASP.NET操作MYSQL数据库，以及操作数据库方法的封装

一、连接MYSQL数据库

string conn = "Data Source=127.0.0.1;User ID=root;Password=wjx12345;DataBase=test;CharSet=utf8";
MySqlConnection con = new MySqlConnection(conn);
con.Open();
Label1.Text = "SqlConnection连接成功!";
con.Close();

效果如图所示:

二、对MYSQL数据库的增删查改

首先，为了便于操作，在项目中新建文件夹把对数据库的操作封装成一个类（记得要对类属性要选择编译，不然无法在其他地方引用）

namespace class4.App_Code
{
    public class DbUtils
    {
        private MySqlConnection conn = null;
        private MySqlCommand cmd = null;
        private MySqlDataReader reader = null;

        public DbUtils()
        {
            string connstr = "Data Source=127.0.0.1;User ID=root;Password=wjx12345;DataBase=test;CharSet=utf8";
            conn = new MySqlConnection(connstr);
        }

        public void CreateCommand(string sql)
        {
            conn.Open();
            cmd = new MySqlCommand(sql, conn);
        }

        //插入,修改，删除数据方法
        public int getExecute()
        {
            int res = -1;
            try
            {
                res = cmd.ExecuteNonQuery();
            }catch(MySqlException ex)
            {
                Console.WriteLine("操作失败!" + ex.Message);
            }
            conn.Close();
            return res;
        }

        //查询数据
        public DataTable getSelect()
        {
            DataTable dt = new DataTable();
            using (reader = cmd.ExecuteReader(CommandBehavior.CloseConnection))
            {
                dt.Load(reader);
            }
            return dt;
        }

    }
}

好了，有了之前的操作，可以方便的操作mysql数据库了。

例如实现:列出所有学号并可以查询，插入学生，更新学号，删除等一系列操作。

相关代码:

namespace class4
{
    public partial class test2 : System.Web.UI.Page
    {
        private DbUtils dbUtils = new DbUtils();
        private string sql = "";

        protected void Page_Load(object sender, EventArgs e)
        {
            if (!IsPostBack)
            {
                sql = "select * from students";
                dbUtils.CreateCommand(sql);
                DataTable dt = dbUtils.getSelect();
                for(int i = 0; i < dt.Rows.Count; i++)
                {
                    ListItem li = new ListItem();
                    li.Text = "" + dt.Rows[i][0];
                    li.Value = "" + dt.Rows[i][0];
                    DropDownList1.Items.Add(li);
                }
            }
            
        }

        //查询数据逻辑
        protected void Button1_Click(object sender, EventArgs e)
        {
            string sql = "select * from students where uid=" + DropDownList1.SelectedItem.Value;
            dbUtils.CreateCommand(sql);
            DataTable dt = dbUtils.getSelect();
            if(dt != null)
            {
                Label3.Text = "学号:" + dt.Rows[0][0] + "  姓名:" + dt.Rows[0][1];
            }
            else
            {
                Label3.Text = "未查询出结果";
            }
        }

        //添加按钮逻辑
        protected void Button2_Click(object sender, EventArgs e)
        {
            string uid = TextBox1.Text;
            string uname = TextBox2.Text;
            string sql = "insert into students(uid,uname) values(" + uid + ",'" + uname + "')";
            dbUtils.CreateCommand(sql);
            int res = dbUtils.getExecute();
            Label3.Text = "有" + res + "条记录受影响";
            TextBox1.Text = "";
            TextBox2.Text = "";
        }

        //更新按钮逻辑
        protected void Button3_Click(object sender, EventArgs e)
        {
            string OldId = TextBox3.Text;
            string NewId = TextBox4.Text;
            string sql = "update students set uid = " + NewId + " where uid = " + OldId;
            dbUtils.CreateCommand(sql);
            int res = dbUtils.getExecute();
            Label3.Text = "有" + res + "条记录受影响";
            TextBox3.Text = "";
            TextBox4.Text = "";
        }

        //删除按钮逻辑
        protected void Button4_Click(object sender, EventArgs e)
        {
            string uid = TextBox5.Text;
            string sql = "delete from students where uid = " + uid;
            dbUtils.CreateCommand(sql);
            int res = dbUtils.getExecute();
            Label3.Text = "有" + res + "条记录受影响";
            TextBox5.Text = "";
        }


    }
}