从textarea的输出中删除空行

function removeEmptyLines(text) {
  const lines = text.split('\n');
  const nonEmptyLines = lines.filter(line => line.trim() !== '');
  return nonEmptyLines.join('\n');
}

const textarea = document.querySelector('textarea');
textarea.addEventListener('input', () => {
  textarea.value = removeEmptyLines(textarea.value);
});