link copy to clipboard

by alexd0001

HTML

<input type="text" id="val" value="4" />
<input type="button" value="2 + 2 =" onclick="copyToClipboard();" />

CSS

#val {
  opacity: 0;
  position: absolute;
  pointer-events: none;
}

JavaScript

function copyToClipboard() {
  document.getElementById('val').select();
  document.execCommand('Copy');
}