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linq-to-sqlwindows-mobilecompact-framework

Missing Linq namespaces (Linq to sql, compact framework)

I spent this morning in trying to figure out where the system.linq.expressions namespace is. The following is what I did:

  1. In VS 2008, Create a new C#/Smart Device/Windows Mobile 6 Professional SDK/.NET CF v3.5/Class Library

  2. Used SqlMetal (in Program Files/Microsoft SDKs/Windows/v6.0A/Bin) to generate the data context.

  3. Added the data context .cs file into the project.

  4. Compile and many errors for missing namespaces: System.Data.Linq, System.Data.Linq.Mapping, System.Linq.Expressions

  5. After some research added System.Data.Linq.dll in c:\Program Files\Reference Assemblies\Microsoft\Framework\v3.5 (The dll was not directly listed when I choose to add reference and I used "browse" tab to finally located the one, which is for normal framework)

  6. Compile again, less errors, but still System.Linq.Expressions namespace is missing.

The document says System.Linq.Expressions is in System.Core.dll but it seems my System.Core.dll (located in Program Files\Microsoft.NET\SDK\CompactFramework\v3.5\WindowsCE) contains much less namespace than document says.

Thanks in advance!

Solution

  • The Compact Framework does not support LINQ to SQL. All objects in the documentation for System.Data.Linq confirms this by being completely devoid of the "supported in the CF" icon. For example, look over at the docs for DataTable, which is supported. You'll see a little icon by each supported method/property.

    You cannot "add" support by simply referencing a desktop assembly like you did in your step 5. The CF cannot consume full framework assemblies, for a variety of reasons.