Friendly url of media file

mediafile.sitecore

https://community.sitecore.net/technical_blogs/b/sitecorejohn_blog/posts/sitecore-idiosyncrasies-media-urls

<configuration xmlns:patch="http://www.sitecore.net/xmlconfig/">
  <sitecore>
    <settings>
      <setting name="Media.RequestExtension">
        <patch:attribute name="value"></patch:attribute>
      </setting>
      <setting name="Media.MediaLinkPrefix">
        <patch:attribute name="value">-/media</patch:attribute>
      </setting>
    </settings>
    <customHandlers>
      <handler trigger="-/media/" handler="sitecore_media.ashx"/>
    </customHandlers>
  </sitecore>
</configuration>

string mediaUrl = Sitecore.StringUtil.EnsurePrefix( '/',
  Sitecore.Resources.Media.MediaManager.GetMediaUrl(mediaItem));