title: Remove first bytes from QByteArray
body: <p>I want to write a function in which QByteArray is input to the function.
  I want to remove some header from receive data and store it into global QByteArray. </p>
  
  <pre><code>void abc::CopyData(const QByteArray &amp;data)
  {
      switch(RequestPacketCount)
      {
          case REQUEST_FIRST_PACKET:
          {
              ByteArrayData = data;
          }
              break;
          case REQUEST_SECOND_PACKET:
          case REQUEST_THIRD_PACKET:
              ByteArrayData.append(data);
      }
  }
  </code></pre>
  
  <p>I want to remove 'n' no. of byte from start of 'data' and store remaining data  into 'ByteArrayData'</p>
  
  <p>Thanks in advance. </p>