title: how to find \n in string in dart
body: <p>I have a json file from which I read an array of objects.</p>
  
  <p>Now I have situation where, if some object contains <code>\n</code>, then I have to do some extra operations. To check whether the objects contain <code>\n</code>, or not, I do the following...</p>
  
  <pre><code>String normalString = 'somethin \n and something';    
  String jsonString = jsonFileData['some_field'];    
  print(normalString.contains('\n')); //true 
  print(jsonString.contains('\n')); // false
  </code></pre>
  
  <p>If I do <code>string.contains()</code> with simple string it returns <code>true</code>, but if I check check the json file as a string <code>false</code> is returned.</p>
  
  <p>Why is this so?</p>