下面我们来具体看一下attr的用法:
一、attr(name):取得第一个匹配元素的属性值。通过这个方法可以方便地从第一个匹配元素中获取一个属性的值。如果元素没有相应属性,则返回 undefined 。其中name为string.下面我用一个img元素演示一下这种用法:
//html文件中

//我们可以用attr获得img元素的src属性,具体用法如下:
$(function(){
var imgSrc = $("img").attr('src');
alert(imgSrc); //显示 a.gif
})
二、attr(key,value):为所有匹配的元素设置一个属性值。key为string属性名,value为object属性值,用法演示:
//html文件中
//使用此方法设置img的src属性
$(function(){
$("img").attr('src', 'a.gif'); //文件中显示

})
三、attr(properties):这是一种在所有匹配元素中批量设置很多属性的最佳方式。 注意,如果你要设置对象的class属性,你必须使用'className' 作为属性名。或者你可以直接使用.addClass( class ) 和 .removeClass( class ).
//文件中

$(function(){
$("img").attr({src:'a.gif', title:'this is a image', className: 'filter'});
})
// 显示为

四、attr(key, fn):为所有匹配的元素设置一个计算的属性值。不提供值,而是提供一个函数,由这个函数计算的值作为属性值。
//文件中

$(function(){
$("img").attr('title', function(){ return this.src }); //显示

})
以上介绍的是attr的一些用法,下面是removeAttr的用法 remove故明思意就是移除的意思,从每一个匹配的元素中删除一个属性。它的具体用法就是:
//文档中

$(function(){
$("img").removeAttr('title'); //显示

})
以上介绍了attr和removeAttr的基本用法,在实际的工作中还会遇到一些更为复杂的应用,这就需要我们掌握基本用法的同时,多多总结和尝试其他用法。

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