-5
我很好奇为什么元素被替换,而不是添加在div的末尾......?为什么元素被替换
<!DOCTYPE html>
<html>
<body>
<h1>JavaScript in Body</h1>
<div id="demo">
<h1>A paragraph will appear below</h1>
</div>
<button type="button" onclick='document.getElementById("demo").innerHTML = "<p>My First JavaScript</p>"'>Insert a paragraph</button>
</body>
</html>