MySql在Visual Studio 2012中不起作用：无法findtypes或名称空间名称“MySql”

鉴于此代码：

using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Text; using System.Windows.Forms; //Include mysql client namespace. using MySql.Data.MySqlClient; // That one doesn't work !!! using System.Configuration; namespace CSharpMySqlSample { public partial class frmMySqlSample : Form { //Read connection string from application settings file string ConnectionString = ConfigurationSettings.AppSettings["ConnectionString"]; MySqlConnection connection; MySqlDataAdapter adapter; DataTable DTItems; public frmMySqlSample() { InitializeComponent(); } private void frmMySqlSample_Load(object sender, EventArgs e) { //Initialize mysql connection connection = new MySqlConnection(ConnectionString); //Get all items in datatable DTItems = GetAllItems(); //Fill grid with items dataGridView1.DataSource = DTItems; } //Get all items from database into datatable DataTable GetAllItems() { try { //prepare query to get all records from items table string query = "select * from items"; //prepare adapter to run query adapter = new MySqlDataAdapter(query, connection); DataSet DS = new DataSet(); //get query results in dataset adapter.Fill(DS); // Set the UPDATE command and parameters. adapter.UpdateCommand = new MySqlCommand( "UPDATE items SET ItemName=@ItemName, Price=@Price, AvailableQuantity=@AvailableQuantity, Updated_Dt=NOW() WHERE ItemNumber=@ItemNumber;", connection); adapter.UpdateCommand.Parameters.Add("@ItemNumber", MySqlDbType.Int16, 4, "ItemNumber"); adapter.UpdateCommand.Parameters.Add("@ItemName", MySqlDbType.VarChar, 100, "ItemName"); adapter.UpdateCommand.Parameters.Add("@Price", MySqlDbType.Decimal, 10, "Price"); adapter.UpdateCommand.Parameters.Add("@AvailableQuantity", MySqlDbType.Int16, 11, "AvailableQuantity"); adapter.UpdateCommand.UpdatedRowSource = UpdateRowSource.None; // Set the INSERT command and parameter. adapter.InsertCommand = new MySqlCommand( "INSERT INTO items VALUES (@ItemNumber,@ItemName,@Price,@AvailableQuantity,NOW());", connection); adapter.InsertCommand.Parameters.Add("@ItemNumber", MySqlDbType.Int16, 4, "ItemNumber"); adapter.InsertCommand.Parameters.Add("@ItemName", MySqlDbType.VarChar, 100, "ItemName"); adapter.InsertCommand.Parameters.Add("@Price", MySqlDbType.Decimal, 10, "Price"); adapter.InsertCommand.Parameters.Add("@AvailableQuantity", MySqlDbType.Int16, 11, "AvailableQuantity"); adapter.InsertCommand.UpdatedRowSource = UpdateRowSource.None; // Set the DELETE command and parameter. adapter.DeleteCommand = new MySqlCommand( "DELETE FROM items " + "WHERE ItemNumber=@ItemNumber;", connection); adapter.DeleteCommand.Parameters.Add("@ItemNumber", MySqlDbType.Int16, 4, "ItemNumber"); adapter.DeleteCommand.UpdatedRowSource = UpdateRowSource.None; //return datatable with all records return DS.Tables[0]; } catch (Exception ex) { MessageBox.Show(ex.Message); } return null; } private void btnSave_Click(object sender, EventArgs e) { try { //Save records in database using DTItems which is datasource for Grid adapter.Update(DTItems); //Refresh grid DTItems = GetAllItems(); dataGridView1.DataSource = DTItems; MessageBox.Show("Items saved successfully..."); } catch(Exception ex) { MessageBox.Show(ex.Message); } } private void btnDelete_Click(object sender, EventArgs e) { if (dataGridView1.SelectedRows.Count > 0) { //Delete a row from grid first. dataGridView1.Rows.Remove(dataGridView1.SelectedRows[0]); //Save records again. This will delete record from database. adapter.Update(DTItems); //Refresh grid. Get items again from database and show it in grid. DTItems = GetAllItems(); dataGridView1.DataSource = DTItems; MessageBox.Show("Selected item deleted successfully..."); } else { MessageBox.Show("You must select entire row in order to delete it."); } } } } 

编译后我得到：

 error CS0246: The type or namespace name 'MySqlConnection' could not be found (are you missing a using directive or an assembly reference?) 

但是我检查了连接器：

它的安装

• 多核心架构上的multithreading
• C＃ – 如何从静态主要方法调用一个方法
• 在c＃windows应用程序中find打开的窗体
• 为什么库在Windows上实现自己的基本locking？
• 我怎么知道HWND是否是桌面？

那么怎么了？

谢谢

 PM> Install-Package MySql.Data 

  <assemblyIdentity name="MySql.Data" publicKeyToken="c5687fc88969c44d" culture="neutral" /> <assemblyIdentity name="MySql.Web" publicKeyToken="c5687fc88969c44d" culture="neutral" />