Question

Is there an equivalent “*” for Contains(““)? I’m using some wildcards for filtering and if there isn’t a filter applied then I need to return all?

string[] filter = {1,2};  // This is dynamic could be filtered values or {} empty.

// This works for filtering by products (1,2)
db.Products.Where(x => filter.Contains(x.ProdId));

What I really need to achieve is something like this:

// If the filter is empty get all results...if there is a filter passed the filter values in for select
db.Products.Where(x => x.ProdId.Contains(filter.Length == 0 ? "*" : filter);

Answer 1

Use this:

var result = db.Products.AsQueryable();

if(filter.Any())
    result = result.Where(x => filter.Contains(x.ProdId));

If the filter is not the only where condition, that’s not a problem at all, you can define multiple Wheres for your query:

var result = db.Products.Where(x => SomeCondition(x));

if(filter.Any())
    result = result.Where(x => filter.Contains(x.ProdId));