title: Referencing Namespaces in C# headers with using-directives
body: <p>I want to have using codes like as shown below, for example:</p>
  
  <pre><code>using System;
  using System.Collections.Generic;
  using System.Linq;
  using System.Text;
  using System.Diagnostics;
  using System.IO;
  </code></pre>
  
  <p>but this c# code below (taken from the question <a href="https://stackoverflow.com/questions/11060019/command-prompt-output-being-read-as-empty-string">Command prompt output being read as empty string</a>) has no headers like above to compiled with csc.exe in cmd console and i tried to comment on that thread but a requirement of 50 reputation is needed and i had no VB studio IDE yet and im new to learning C#.</p>
  
  <pre><code>var output = new StringBuilder();
  var error = new StringBuilder();
  
  cmd.OutputDataReceived += (o, e) =&gt; output.Append(e.Data);
  cmd.ErrorDataReceived += (o, e) =&gt; error.Append(e.Data);
  
  cmd.Start();
  cmd.BeginOutputReadLine();
  cmd.BeginErrorReadLine();
  cmd.WaitForExit();
  </code></pre>