MYourDataContext.AllInstances.YourInlineTableValuedFunctionString = (t1,t2) =>
{
var resultsList = new List<YourInlineTableValuedFunctionResult>
                  {
                     new YourInlineTableValuedFunctionResult(),
                     new YourInlineTableValuedFunctionResult()
                  };
return resultsList.AsQueryable();
}

http://msdn.microsoft.com/en-us/library/system.data.linq.datacontext.aspx

This example is for an  inline table value function with one string parameter
t1 is of type YourDataContext and t2 is of type string(hence the name of the mole method)

How to mock an inline table valued function in LINQ to SQL

c#

C#