Web projects do not support the solution of LINQ.

My project is from. upgrade net2.0. net3.5, other projects can use LINQ, and only web projects cannot be used. I guess it is web. after comparison, you only need. add the following config:Code:

 

<System. codedom>

<Compilers>

compiler language =" C #; CS; CSHARP " extension =" . CS " WarningLevel =" 4 "

Type="Microsoft. CSHARP. csharpcodeprovider, system, version = 2.0.0.0, culture = neutral, publickeytoken = b77a5c561934e089">

<Provideroption Name="Compilerversion" Value="V3.5"/>

<Provideroption Name="Warnaserror" Value="False"/>

</Compiler>

compiler language =" Vb; vbs; VisualBasic; VBScript " extension =" . VB " WarningLevel =" 4 "

Type="Microsoft. VisualBasic. vbcodeprovider, system, version = 2.0.0.0, culture = neutral, publickeytoken = b77a5c561934e089">

<Provideroption Name="Compilerversion" Value="V3.5"/>

<Provideroption Name="Optioninfer" Value="True"/>

<Provideroption Name="Warnaserror" Value="False"/>

</Compiler>

</Compilers>

</System. codedom>

 

Hope to be useful to friends who have the same problem.