JSFiddle - React, Tailwind, and code Playground

by parksd

JavaScript

document.addEventListener('copy', function(e) {
  // e.clipboardData is initially empty, but we can set it to the
  // data that we want copied onto the clipboard.
  e.clipboardData.setData('text/plain', 'Hello, world!');
  e.clipboardData.setData('text/html', '<b>Hello, world!</b>');

  // This is necessary to prevent the current document selection from
  // being written to the clipboard.
  e.preventDefault();
});

document.addEventListener('paste', function(e) {
  // e.clipboardData contains the data that is about to be pasted.
  if (e.clipboardData.types.indexOf('text/html') > -1) {
    var oldData = e.clipboardData.getData('text/html');
    var newData = '<b>Ha Ha!</b> ' + oldData;

    // Since we are canceling the paste operation, we need to manually
    // paste the data into the document.
    alert(newData);

    // This is necessary to prevent the default paste action.
    e.preventDefault();
  }
});