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<int>, 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<Func<Segment, bool>> expression =
    s => s.RouteIds.Contains(int.Parse(this.ddlRouteNames.SelectedValue));