public void setupFilters()
{
collection = new ObservableCollection<NOS>()
{
new NOS( "Group1", "Item1" ),
new NOS( "Group1", "Item2" ),
new NOS( "Group1", "Item3" ),
new NOS( "Group2", "Item4" ),
new NOS( "Group2", "Item5" ),
new NOS( "Group2", "Item6" ),
};
operation = new GroupByOperation<NOS, string>(new OperationContext(),
Expression.Call(
typeof(Queryable).GetMethods()
.Where(i => i.Name == "GroupBy")
.Where(i => i.IsGenericMethodDefinition)
.Where(i => i.GetGenericArguments().Length == 2)
.Select(i => i.MakeGenericMethod(typeof(NOS), typeof(string)))
.Where(i => i.GetParameters().Length == 2)
.Where(i => i.GetParameters()[1].ParameterType == typeof(Expression<Func<NOS, string>>))
.Single(),
new ObservableQuery<NOS>(collection).Expression,
Expression.Lambda<Func<NOS, string>>(
Expression.MakeMemberAccess(
Expression.Parameter(typeof(NOS), "p"),
typeof(NOS).GetProperty("Value1")),
Expression.Parameter(typeof(NOS), "p"))));
buffer = operation.AsObservableQuery().ToObservableView().ToBuffer();
}
