- <!DOCTYPE html>
- <html>
- <head lang="en">
- <meta charset="UTF-8">
- <title>
- 列表框,下拉菜单的增删改操作
- </title>
- <script type="text/javascript">
- function createSelect() {
- //创建
- var select = document.createElement("select");
- select.id = "city";
- var body = document.getElementById("test");
- body.appendChild(select);
- //创建五个option
- for (var i = 1; i < 5; i++) {
- var opt = new Option("值" + i, "value" + i);
- select.options[i] = opt;
- }
- }
- function delone() {}
- function clearAll() {
- //只要把options的长度改为0就可以的
- var city = document.getElementById("city");
- city.options.length = 0;
- }
- </script>
- </head>
- <body id="test">
- <input type="button" value="创建一个城市列表框" onclick="createSelect()" />
- <input type="button" value="一条条删除列表框内容" onclick="delone()" />
- <input type="button" value="一次性清空列表框内容" onclick="clearAll()" />
- </body>
- </html>
来源: http://www.bubuko.com/infodetail-1948467.html