How to build an IEnumerable.Contains() Expression?

Question

I\'m currently working with ASP Dynamic Data for the first time and I\'m trying to build a filter. Our users have a need to locate items in a list based upon whether or not

Answer 1

There are two problems in your code:

1. Your parameters are backwards. The first parameter has to be the collection, the second the item you're searching for.
2. Your type argument is IEnumerable, when it should be just int.

So, the fixed code is:

var callExpression = Expression.Call(
    typeof(Enumerable), "Contains", new[] { typeof(int) }, me, ce);

But it seems all the parts of your expression are not actually dynamic, so maybe something like that following would work too:

Expression> expression =
    s => s.RouteIds.Contains(int.Parse(this.ddlRouteNames.SelectedValue));