title: http webrequest content type null
body: <p>is it necessary to mention content-type in http header while uploading the file. i tried using c#. i had set it "image/png" while uploading a pdf file and when i downloaded the uploaded file, the pdf file was perfect. it didn't get corrupted.</p>
  
  <p>so what is the role of specifying content-type in http header.
  can it be null or any other wrong value.</p>
  
  <p>because the application that i am making, user will just give the file and and i just need to upload it.</p>
  
  <p>any help highly appreciated. thanks in advance.</p>