用javascript替换图片
我想用javascript替换gif文件.我发现下面的方法.有什么办法可以将javascript标记放在img标记之前?
I want to replace the gif file by javascript. I find the method below. Is there any way i can place the javascript tag before the img tag?
<img class="myImg" src="compman.gif" width="107" height="98">
<script>
document.getElementsByClassName("myImg")[0].src = "hackanm.gif";
</script>
在文档就绪"之前，无法安全地操纵页面.使用jquery的$(document).ready()，它将等待直到页面被加载并准备好进行操作之后再执行(无论它在页面上的什么位置).示例:
A page can't be manipulated safely until the document is "ready." Using jquery's $(document).ready(), it Will wait until the page is loaded and ready to be manipulated before executing (no matter where it is on the page). Example:
<script>
$(document).ready(function() {
document.getElementsByClassName("myImg")[0].src = "hackanm.gif";
});
</script>
<img class="myImg" src="compman.gif" width="107" height="98">
然后，您还可以在jquery中利用选择器(例如，$(".class")其中class是您的类，或者$("#id")其中id是id)，并将代码更改为:
You could also then leverage selectors inside jquery (e.g. $(".class") where class is your class, or $("#id") where id is the id) and change the code to:
<script>
$(document).ready(function() {
$(".myImg").attr('src',"hackanm.gif");
});
</script>
<img class="myImg" src="compman.gif" width="107" height="98">
如果您以后还要在javascript中进行更改，甚至可以将其存储在变量中！
And further you could even store it in a variable if you wanted to change it later on in javascript as well!
<script>
$(document).ready(function() {
var myImg = $(".myImg");
var newImg = "hackanm.gif";
myImg.attr('src', newImg);
});
</script>
<img class="myImg" src="compman.gif" width="107" height="98">
希望这可以帮助您学习javascript内的一些新技巧！编码愉快！
Hope this helps you learn a few new tricks inside javascript! Happy coding!