# System.Net.Http.Headers

``` diff
 namespace System.Net.Http.Headers {
+    public readonly struct HeaderStringValues : IEnumerable, IEnumerable<string>, IReadOnlyCollection<string> {
+        public int Count { get; }
+        public HeaderStringValues.Enumerator GetEnumerator();
+        IEnumerator<string> System.Collections.Generic.IEnumerable<System.String>.GetEnumerator();
+        IEnumerator System.Collections.IEnumerable.GetEnumerator();
+        public override string ToString();
+        public struct Enumerator : IDisposable, IEnumerator, IEnumerator<string> {
+            public string Current { get; }
+            object System.Collections.IEnumerator.Current { get; }
+            public void Dispose();
+            public bool MoveNext();
+            void System.Collections.IEnumerator.Reset();
+        }
+    }
     public abstract class HttpHeaders : IEnumerable, IEnumerable<KeyValuePair<string, IEnumerable<string>>> {
+        public HttpHeadersNonValidated NonValidated { get; }
     }
+    public readonly struct HttpHeadersNonValidated : IEnumerable, IEnumerable<KeyValuePair<string, HeaderStringValues>>, IReadOnlyCollection<KeyValuePair<string, HeaderStringValues>>, IReadOnlyDictionary<string, HeaderStringValues> {
+        public int Count { get; }
+        IEnumerable<string> System.Collections.Generic.IReadOnlyDictionary<System.String,System.Net.Http.Headers.HeaderStringValues>.Keys { get; }
+        IEnumerable<HeaderStringValues> System.Collections.Generic.IReadOnlyDictionary<System.String,System.Net.Http.Headers.HeaderStringValues>.Values { get; }
+        public HeaderStringValues this[string headerName] { get; }
+        public bool Contains(string headerName);
+        public HttpHeadersNonValidated.Enumerator GetEnumerator();
+        IEnumerator<KeyValuePair<string, HeaderStringValues>> System.Collections.Generic.IEnumerable<System.Collections.Generic.KeyValuePair<System.String,System.Net.Http.Headers.HeaderStringValues>>.GetEnumerator();
+        bool System.Collections.Generic.IReadOnlyDictionary<System.String,System.Net.Http.Headers.HeaderStringValues>.ContainsKey(string key);
+        bool System.Collections.Generic.IReadOnlyDictionary<System.String,System.Net.Http.Headers.HeaderStringValues>.TryGetValue(string key, out HeaderStringValues value);
+        IEnumerator System.Collections.IEnumerable.GetEnumerator();
+        public bool TryGetValues(string headerName, out HeaderStringValues values);
+        public struct Enumerator : IDisposable, IEnumerator, IEnumerator<KeyValuePair<string, HeaderStringValues>> {
+            public KeyValuePair<string, HeaderStringValues> Current { get; }
+            object System.Collections.IEnumerator.Current { get; }
+            public void Dispose();
+            public bool MoveNext();
+            void System.Collections.IEnumerator.Reset();
+        }
+    }
 }
```

