Sample code for put rest service that simulates a form.

 I am using a service that simulates forms for POST and GET,  I have to execute a POST and I am struggling to do that.  The code to post is below.  I would appreciate any help I can get.
Thanks!!!
Hsmith825
a snipet of the Post code:
{
    string strBoundary = CreateGuid(32);
    StringBuilder bodyPrefixStringBuilder = new StringBuilder();
    // Setting the Access__key parameter
    bodyPrefixStringBuilder.Append("--" + strBoundary + newLine);
    bodyPrefixStringBuilder.Append("Content-Disposition: form-data; name=\"access_key\"" + newLine + newLine + mediaAccess_key.Value + newLine);
    // Creating MemoryStream
    Stream memStream = new System.IO.MemoryStream();
    // Adding the body prefix
    byte[] bodyPrefixBytes = ...