Some details in jquery selector-JS Tutorial-php.cn

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Some details in jquery selector

伊谢尔伦

Dec 10, 2016 am 09:45 AM

jquery

1. Visibility filter selector

:hidden selects all invisible elements. For example:$(":hidden") means to select all invisible elements. Includes:

<input type="hidden" />
<div style="display:none;"></div>
<div style="visibity:hidden"></div>

Annotation content on the html page /**/,

, (if this tag is on the page), , <script src="*.js"></script>, <script type="text/JavaScript"></script>, <style type="text/css"></style> <br> and other elements. If you only want to remove the <input> element, you can use $("input:hidden"). Note that there is no space between input:hidden. We will explain the difference between the presence and absence of spaces later; <br>Verification is as follows: <br>Verification page code: <pre class='brush:php;toolbar:false;'><!DOCTYPE html> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>测试jQuery选择器</title> <script src="Scripts/jquery-1.7.1.js"></script> <style type="text/css"> .test { background-color: yellow; } </style> </head> <body> <input type="hidden" value="hidden"/> <div style="display:none"></div> <script type="text/javascript"> var $hidden1 = $(":hidden"); var $hidden2 = $("input:hidden"); var len1 = $hidden1.length; var len2 = $hidden2.length; console.log("$(':hidden').length:"+len1); console.log("$('input:hidden').lengh:" + len2); $.each($hidden1, function () { console.log(this.nodeName+":"+ this.innerHTML); }); $.each($hidden2, function () { console.log(this.nodeName + ":" + this.innerHTML); }); </script> </body> </html></pre><p>The output result is as follows:</p><pre class='brush:php;toolbar:false;'>$(':hidden').length:8 $('input:hidden').lengh:1 HEAD: <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <title>测试jQuery选择器</title> <script src="Scripts/jquery-1.7.1.js"></script> <style type="text/css"> .test { background-color: yellow; } </style> META: TITLE:测试jQuery选择器 SCRIPT: STYLE: .test { background-color: yellow; } INPUT: DIV: SCRIPT: var $hidden1 = $(":hidden"); var $hidden2 = $("input:hidden"); var len1 = $hidden1.length; var len2 = $hidden2.length; console.log("$(':hidden').length:"+len1); console.log("$('input:hidden').lengh:" + len2); $.each($hidden1, function () { console.log(this.nodeName+":"+ this.innerHTML); }); $.each($hidden2, function () { console.log(this.nodeName + ":" + this.innerHTML); }); INPUT:</pre><p style="margin: 0.8em 0px; padding: 0px; box-sizing: border-box; font-weight: 100; color: rgb(85, 85, 85); font-family: " microsoft yahei line-height: white-space: normal widows: background-color: rgb>2. Whether there are spaces in the selector</p> <p>The spaces in the selector cannot be ignored. The presence or absence of spaces will get different results. Look at the example below: </p><pre class='brush:php;toolbar:false;'><!DOCTYPE html> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>测试jQuery选择器</title> <script src="Scripts/jquery-1.7.1.js"></script> <style type="text/css"> .test { background-color: yellow; } </style> </head> <body> <div class="test"> <div style="display:none">a</div> <div style="display:none">b</div> <div style="display:none">c</div> <div class="test" style="display:none">d</div> </div> <div class="test" style="display:none;">e</div> <div class="test" style="display:none">f</div> <script type="text/javascript"> var $t1 = $(".test :hidden");//带空格 var $t2 = $(".test:hidden");//不带空格 var len1 = $t1.length; var len2 = $t2.length; console.log("$('.test :hidden').length:" + len1); console.log("$('.test:hidden').length:" + len2); $.each($t1, function () { console.log(this.nodeName+":"+ this.innerHTML); }); console.log(); $.each($t2, function () { console.log(this.nodeName + ":" + this.innerHTML); }); </script> </body> </html></pre><p>The output result is as follows: </p><pre class='brush:php;toolbar:false;'>$('.test :hidden').length:4 $('.test:hidden').length:3 DIV:a DIV:b DIV:c DIV:d DIV:d DIV:e DIV:f</pre><span class="hljs-tag" style="color: rgb(0, 102, 102); box-sizing: border-box; font-family: " source code pro monospace line-height: white-space: pre widows: background-color: rgba><p>The reason why there are different results is because the descendant selector and filter selector are different. <br>$(".test :hidden") with spaces selects the hidden elements in the element with class "test", which is equivalent to .class *:hidden and is similar to the expression of css. </p> <p>$(".test:hidden") without spaces selects the hidden element whose class is "test". </p></span>

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