title: Vue.js value bind with prefix and suffix
body: <p>I tried binding a value to an input using a variable that has been declared in the data object, but I also need to add a prefix and a suffix </p>
  
  <pre><code>&lt;input id="topnavback", v-bind:value="rgb({{themestopnavback}})", class="jscolor"/&gt;
  </code></pre>
  
  <p>The value themetopnavback is the value defined in data and I want to put the rgb with bracktes around it. </p>
  
  <p>But this always causes the whole page not to render the DOM which only occurs if you try to access a Vue variable which isn't existing in the data object. Is this just wrong or isn't it possible to bind a value with additional strings? </p>
  
  <p>Thanks in advance</p>