Question

I have this query wit a group join:

    foreach (var item in someList)
    {
                    var result = (from t1 in someContext.Table1
                                  join t2 in someContext.Table2 on new { t1.SomeID, item.SomeName} equals new {t2.SomeID, t2.SomeName} into j1 
                                  ...
    }

I would like to know if it is possible to have a group join as above?

new { t1.SomeID, item.SomeName} equals new {t2.SomeID, t2.SomeName}

item.SomeName comes from the list i am iterating through.

If not, how would i change the statement to get the desired results?

Answer 1

The types of the properties used with the equals expression must match. So for example is Table1.SomeID is Int32 and Table2.SomeID is Nullable<Int32>, then they don’t match.

EDIT

foreach (var item in someList)
    {
       var someName = item.SomeName;
       var result = (from t1 in someContext.Table1
                     join t2 in someContext.Table2 on 
                               new { t1.SomeID, SomeName = someName} 
                        equals new { t2.SomeID, t2.SomeName} into j1 
                                  ...
    }

Also check item.SomeName is same type as t2.SomeName