Content length is not showing in HTTP response header
<p>Accept-Ranges:bytes</p>

<p>Cache-Control:max-age=1296915</p>

<p>Connection:Keep-Alive</p>

<p>Content-Encoding:gzip</p>

<p>Content-Type:application/pdf</p>

<p>Date:Mon, 27 Jun 2016 07:24:58 GMT</p>

<p>ETag:"9c96c69837a1d11:0-gzip"</p>

<p>Keep-Alive:timeout=15, max=100</p>

<p>Last-Modified:Thu, 28 Apr 2016 10:20:32 GMT</p>

<p>Server:Apache</p>

<p>Transfer-Encoding:chunked</p>

<p>Vary:Accept-Encoding</p>

<p>X-Powered-By:ASP.NET</p>

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<p>I want to show content length in response header</p>