Looping through Model Collection and filter a query in asp.net mvc

Question

I Have a model in my Web-Application like this:

class MyClass 
{
    int ID;
    List<AnotherClass> foo {get; set;}
}

class AnotherClass 
{
    int ID;
    string bar;
}

I also have a list of filter-strings given by the user.

List<string> filter = new List<string> { "foo", "bar" } //as example

What I want is to filter MyClass by the given strings like this:

var result = context.MyClass.Include(mc => mc.foo);
result = result.Where(x => filter.Any(f => f == x.foo.Select(d => d.bar)));

The Problem is: Select() returns a List of strings and I can't compare a string with a list of strings.

Anyone an idea how to fix this issue?

Answer 1

使用Contains

result = result.Where(x => x.foo.Any(i => filter.Contains(i.bar)));

Answer 2

If putting into words what you want is: Find whichever item in result, if any of its inner class items is present in the filter list

Try:

result.Where(item => item.Any(innerItem => filter.Contains(innerItem.bar)))

Or in the other syntax:

var output = (from item in result
              from innerItem in item.foo
              where filter.Contains(innerItem.bar)
              select item);

Answer 3

您可能需要简单的Any和Contains方法，就可以做到这一点。

result.Where(x => x.foo.Any(f=> filter.Contains(f.bar));