title: Set collection to modified Entity Framework
body: <p>How can I set a collection to modified in the same way that I would do</p>
  
  <p><code>_context.Entry(thing).Property(x =&gt; x.MyProperty).isModified = true;</code></p>
  
  <p>like:</p>
  
  <p><code>_context.Entry(thing).Collection(x =&gt; x.MyCollection).isModified = true;</code></p>
  
  <p>EDIT: The purpose of this, is that my collection is a list of objects stored in a lookup table. I will only have a list of stubs with their id's in this collection and I would like to update the relationships without messing with the audit values and whatever else is contains within the lookup objects. 
  For instance, a contact will have multiple contact types, which for whatever reason are complex objects in this scenario. I want to be able to add and remove types using only the FKs and let EF handle the relationship fixups.</p>
  
  <pre><code>public class Contact
  {
     public int Id {get;set;}
     public list&lt;ContactTypes&gt; ContactTypes {get;set;}
     //audit values/other properties
  }
  
  public class ContactType
  {
     public int Id {get;set;}
     public string Value {get;set;}
  }
  </code></pre>