title: Keep updating output with change in Input Value
body: <p>Right now I have a code set up using a switch statement to get input numbers and do the math based on what option is selected eg: if BTC is selected then it will do certain math to convert.</p>
  <p>Now the problem I encounter is I want it to update in my HTML as I change the value but I need to keep changing the option to reload to do math</p>
  <p>Is there a way to constantly do the math while I am changing the input value using the switch statement or do I have to rewrite it?</p>
  <p>my code:</p>
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-js lang-js prettyprint-override"><code>function Calc(val) {
  
    sessionStorage.setItem('SelectedItem', val);
  
    switch (val) {
      case 'BTC':
        {
          out = input.value / 100000000 * 33549;
          output.innerHTML = "$" + " " + out;
          break;
        }
      case 'LTC':
        {
          out = input.value / 100000000 * 134;
          output.innerHTML = "$" + " " + out;
          break;
        }
    }
  }</code></pre>
  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;form name="leftCurrency" method="POST"&gt;
  
    &lt;select name="currenOPT" id="currenOPT" onchange="Calc(this.value);"&gt;
      &lt;option name="Currency" value="USD"&gt;USD&lt;/option&gt;
      &lt;option name="Currency" value="BTC"&gt;BTC&lt;/option&gt;
      &lt;option name="Currency" value="LTC"&gt;LTC&lt;/option&gt;
    &lt;/select&gt;
  
  
  
    &lt;input type="text" name="CurenInput" id="inpVal" onkeyup='saveValue(this);'&gt;
    &lt;input type="submit" name="submit" value="submit"&gt;
  &lt;/form&gt;
  
  &lt;h1 id="output" onchange="reload()"&gt;&lt;/h1&gt;</code></pre>
  </div>
  </div>
  </p>
  <p>Here is a video of what is the code doing right now:</p>
  <p><a href="https://imgur.com/a/clIpl4o" rel="nofollow noreferrer">https://imgur.com/a/clIpl4o</a></p>