<!DOCTYPE HTML><html><head><meta charset="utf-8"><title>练习</title><script> function book() {var asd=prompt("请输入网址:"); if{asd!=null} {window.open(tv,"_blank","width=600,height=400,top=50");} else if(asd=="") {alert("未输入网址");} else if(asd==null) {alert("请输入网址");} }</script></head><body> <form> <input type="button" name="button" onclick="book()" value="点击输入网址" /> </form></body></html>
添加回答
举报
0/150
提交
取消