内容描述：用js代码实现点击按钮对div框架隐藏和显示，点击一次展开div,再次点击隐藏
代码：
<!DOCTYPE html><html lang="en"><head><meta charset="UTF-8"><title>Title</title><style>#div1 {width: 100px;height: 400px;background-color: red;display: none;}</style><script>function f() {var v1 = document.getElementById("div1");if (v1.style.display == "none") {v1.style.display = "block";} else {v1.style.display = "none";}}</script></head><body><input type="button" value="显示隐藏" onclick="f()"><div id="div1"></div></body></html>
效果图：
初始页
点击一次
点击两次
