打開你的項目在項目上右鍵，選擇[管理NuGet程序包]在[瀏覽]選項卡中搜索MySql選擇MySql.Data,在右側勾選安裝的項目后，點擊[安裝]按鈕相應的dll就安裝到項目了var mssb = new MySqlConnectionStringBuilder();MySqlConnection sqlConnect = new MySqlConnection(mssb.ConnectionString);