console 命令行工具 X clear

console

$("p:first").hide();
$("#show").click(function(){
  alert($("#div1").innerHeight());});
  //$("#div1").innerHeight("130px");});

<div id="div1">13</div>
<h1>Property</h1>
<h1>Attribute</h1>
<p id="p1">Paragraph1</p>
<p id="p2">Paragraph2</p>
<button id="show">显示</button>
<button id="hide">隐藏</button>

#div1{
  height:30;
  border: 5px solid;
}