title: How to calculate CheckSum in FIX manually?
body: <p>I have a <code>FixMessage</code> and I want to calculate the checksum manually.</p>
  
  <pre><code>8=FIX.4.2|9=49|35=5|34=1|49=ARCA|52=20150916-04:14:05.306|56=TW|10=157|
  </code></pre>
  
  <p>The body length here is calculated: </p>
  
  <pre><code>8=FIX.4.2|9=49|35=5|34=1|49=ARCA|52=20150916-04:14:05.306|56=TW|10=157|
  0        + 0  + 5  + 5  + 8     + 26                     + 5   + 0  = 49(correct)
  </code></pre>
  
  <p>The checksum is 157 (10=157). How to calculate it in this case?</p>