我了解如何将 web mysql 数据库与 C# windows 窗体应用程序连接起来

Question

昨天，我花了很多时间搜索连接Mysql WEB database 和C# windows form application 的教程，我尝试了很多代码并观看了大约 10 个类似的教程但没有任何帮助，我的意思是它对我没有帮助，因为它没有连接类型我需要...

我想连接这个数据库： Databsae image by lightshot

在这段代码中：

using MySql.Data.MySqlClient;
using System;
using System.Drawing;
using System.IO;
using System.Windows.Forms;

namespace CS_Enginer
{
    public partial class login : Form
    {
        public login()
        {
            InitializeComponent();
        }


        private void textBox1_Enter(object sender, EventArgs e)
        {
            if (textBox1.Text == "Username")
            {
                textBox1.Text = "";
                textBox1.ForeColor = Color.DimGray;
            }

        }

        private void textBox1_Leave(object sender, EventArgs e)
        {
            if (textBox1.Text == "")
            {
                textBox1.Text = "Username";
                textBox1.ForeColor = Color.DimGray;
            }
        }

        private void textBox2_Enter(object sender, EventArgs e)
        {
            if (textBox2.Text == "Password")
            {
                textBox2.Text = "";
                textBox2.ForeColor = Color.DimGray;
                textBox2.UseSystemPasswordChar = true;
            }

        }

        private void textBox2_Leave(object sender, EventArgs e)
        {
            if (textBox2.Text == "")
            {
                textBox2.Text = "Password";
                textBox2.ForeColor = Color.DimGray;
                textBox2.UseSystemPasswordChar = false;
            }
        }

        private void button2_Click(object sender, EventArgs e)
        {

        }

        private void button3_Click(object sender, EventArgs e)
        {
            Application.Exit();
        }

        private void button4_Click(object sender, EventArgs e)
        {
            this.WindowState = FormWindowState.Minimized;
        }

        private void login_MouseDown(object sender, MouseEventArgs e)
        {
        }

        private void login_Load(object sender, EventArgs e)
        {
        }

        private void button1_Click(object sender, EventArgs e)
        {
        }
    }
}

我知道我不应该发布图片，但我不知道如何解释...对此感到抱歉，提前致谢！！！

Answer 1

注意：仅当从网站的 CPANEL 启用到数据库的远程连接时，以下操作才有效。

要连接到数据库，您需要一个连接字符串和库来帮助您连接并从数据库中检索数据。对于 MySql，您可以使用此处提供的 MySql 连接器 - MySql connector

下载后，右键单击您的项目名称并选择“添加”，然后选择“引用”，将连接器的引用添加到您的项目。

添加引用后，导入项目using MySql.Data.MySqlClient;中的类。

现在，您需要形成连接字符串并打开连接，如下所示 -

private void MySqlInteraction()
    {
        string connString = null;
        MySqlConnection mySqlConn;
        // It would be better if the below connection string is provided by the vendor
        // of the database website that you are trying to access as you might not have
        // all the required information
        connString = "server=youronlineserver;database=dbname;uid=root;pwd=abc123;";
        mySqlConn = new MySqlConnection(connString);
        try
        {
            mySqlConn.Open();
            MessageBox.Show ("Connection Open ! ");
            //enter your db querying logic here
            mySqlConn.Close();
        }
        catch (Exception ex)
        {
            MessageBox.Show("Can not open connection ! ");
        }
    }