characters in this string to upper case.
If the string is already in all upper case, this method returns <code>this</code>. <a href="dart-core/String/toUpperCase.html">[...]</a>
                  
</dd>
        <dt id="trim" class="callable">
          <span class="name"><a href="dart-core/String/trim.html">trim</a></span><span class="signature">(<wbr>)
            <span class="returntype parameter">&#8594; <a href="dart-core/String-class.html">String</a></span>
          </span>
                  </dt>
   