写 using System.Web.UI;会出现下面的错误
写 using System.Web.UI;会出现下面的错误
Error 1 The type or namespace name 'UI' does not exist in the namespace 'System.Web' (are you missing an assembly reference?) C:Documents and SettingsdchLocal SettingsApplication DataTemporary ProjectsWindowsApplication1Form2.cs 8 18 WindowsApplication1
应该怎么解决啊?