winform简单缓存类实例

public partial class Form3 : Form{  //缓存类  System.Web.Caching.Cache cache;  public Form3()  {   InitializeComponent();   string SQL = "select top 1000 * from infomation";   DataTable datatable = DBHelper.GetDataTable(SQL, ConnType.Menu);   dataGridView1.DataSource = datatable;   cache = System.Web.HttpRuntime.Cache;   cache.Insert("infomation", datatable);  }  private void button1_Click(object sender, EventArgs e)  {   if (cache != null) {    DataTable table = cache["infomation"] as DataTable;    dataGridView2.DataSource = table;   }     }}