title: How is it possible to edit data inside Windows.Storage.Streams.Buffer
body: <p>in UWP, VPN plugins should encapsulate IP Packets received from the OS by editing the given Buffer(Storage.Streams.Buffer), the buffer is read-only so i can't replace it with another buffer.
  in c++/winrt there is a function named data() inside Buffer which returns uint8 pointer, but there's not such field or function in c#.
  how am i supposed to edit data in Buffer?</p>
  
  <pre><code>        public void Encapsulate(VpnChannel channel, VpnPacketBufferList packets, VpnPacketBufferList encapulatedPackets)
          {
              var packet = packets.RemoveAtBegin();
              var dataBuffer = packet.Buffer; //read-only field
              /*How to edit above buffer without replacing it*/
  
  
          }
  </code></pre>