[Solved]-How would I use an anonymous result type for an expression delegate for LINQ to SQL?-LINQ,C#

var grouping = Linq.Expr((Report_Data g) => new {g.Month, Option1 = g.prop1, Option2 = g.prop2});

if (userParameter == "X") {
    grouping = Linq.Expr((Report_Data g) => new {g.Month, Option1 = g.prop3, Option2 = g.prop4});
} else if(userParameter == "Y") {
    grouping = Linq.Expr((Report_Data g) => new {g.Month, Option1 = g.prop5, Option2 = g.prop6});
}