title: How do I pass a variable inside a POST request URL in JavaScript?
body: <p>I am trying to pass a variable that is derived from a database (and keeps changing) to a fetch URL. I don't want to hard code it in the URL. How do I go about it? Here is the snippet of the code.</p>
  
  <pre><code>  };
    var searchString = amount;
    var payload = JSON.stringify(data);
    var options = {
      'method': 'POST',
      'Content-Type': 'application/json', 
      'payload' : data,
    };
    var url = 'https://......./**amount**/budget_items?token';
    var response = UrlFetchApp.fetch(url, options);
  </code></pre>
  
  <p>I want to pass the <strong>search string variable</strong> but I don't know-how. Any help?</p>