Javascript defer 作用
script src="../cgi-bin/delscript.js" defer/script 中的defer作用是文档加载完毕了再执行脚本,这样回避免找不到对象的问题---有点问题 button id="myButton" onclick="alert('ok')"test/button script myButton.click(); /script script myButton.click();
中的defer作用是文档加载完毕了再执行脚本,这样回避免找不到对象的问题---有点问题
<script><br />myButton.click();<br /></script>
<script><br />myButton.click();<br /></script>
加上 defer 等于在页面完全在入后再执行，相当于 window.onload ，但应用上比 window.onload 更灵活！
defer是脚本程序强大功能中的一个“无名英雄”。它告诉浏览器Script段包含了无需立即执行的代码，并且，与SRC属性联合使用，它还可以使这些脚本在后台被下载，前台的内容则正常显示给用户。
--但是 文档加载完毕了再执行脚本
最后请注意两点：
1、不要在defer型的脚本程序段中调用document.write命令，因为document.write将产生直接输出效果。
2、而且，不要在defer型脚本程序段中包括任何立即执行脚本要使用的全局变量或者函数。
都是defer惹的祸,这两天网站查看全文出错的原因
上周末,本站投放了Google广告,当时为了防止广告的投入延长页面导入的时间,修改了下Google Ad代码,
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