为什么不能直接调用呢?


http://img.mukewang.com/5994f8ff0001d2b413400866.jpg

//为什么不可以直接调用count()函数呢? 如果直接调用的话,就出现上面的错误。
//源码如下:
<!DOCTYPE html>
<html>
 <head>
  <title>浏览器对象</title>  
  <meta http-equiv="Content-Type" content="text/html; charset=gkb"/>   
 </head>
 <body>
  <!--先编写好网页布局-->
  <h2>操作成功</h2>
 
  <script>
	secs = 5;
	function count()
	{
		document.getElementById("sec").innerHTML = secs;
		//document.getElementById("sec").value = secs;
		--secs;
		if(secs == 1)
			location.replace("http://www.imooc.com");
		setTimeout(count, 1000);
	}  
	count();
   	//setTimeout(count, 0); 这样使用就没问题了!
  </script>
    <span><i id="sec">5</i>秒后返回主页<a href="https://www.baidu.com">返回</a></span>
</body>
</html>


AIxer
浏览 1525回答 1
1回答

__innocence

1、定义变量敢不敢使用关键字var secs = 5;2、敢不敢把JavaScript写在文档下面? <!DOCTYPE html> <html>  <head>   <title>浏览器对象</title>     <meta http-equiv="Content-Type" content="text/html; charset=gkb"/>     </head>  <body>   <!--先编写好网页布局-->   <h2>操作成功</h2>     <span><i id="sec">5</i>秒后返回主页<a href="https://www.baidu.com">返回</a></span>          <script>     var secs = 5;     function count()     {         document.getElementById("sec").innerHTML = secs;         //document.getElementById("sec").value = secs;         --secs;         if(secs == 1)             location.replace("http://www.imooc.com");         setTimeout(count, 1000);     }       count();      //setTimeout(count, 0); 这样使用就没问题了!   </script> </body> </html>

慕瓜9220888

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
打开App,查看更多内容
随时随地看视频慕课网APP