Some details in jquery selector

1. Visibility filter selector

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

Annotation content on the html page /**/, 93f0f5c25f18dab9d176bd4f6de5d30e9c3bca370b5104690d9ef395f2c5f8d1, e8e496c15ba93d81f6ea4fe5f55a224403d0e15baf5b7c9d224e5281b47a68fe (if this tag is on the page), b2386ffb911b14667cb8f0f91ea547a7b25a9407cfe693f10872c2a72988c045, f201f3e801a248066d83a5e65188634b2cacc6d41bbb37262a98f745aa00fbf0, 61407f7b7461f346926503a77e36dc2a2cacc6d41bbb37262a98f745aa00fbf0, 769cbb542039d9a75a430d05b5cfa3b6531ac245ce3e4fe3d50054a55f265927
and other elements. If you only want to remove the d5fd7aea971a85678ba271703566ebfd 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;
Verification is as follows:
Verification page code:

The output result is as follows:

$(':hidden').length:8
 $('input:hidden').lengh:1
 HEAD:    
    
    

    
    

 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:

2. Whether there are spaces in the selector

The spaces in the selector cannot be ignored. The presence or absence of spaces will get different results. Look at the example below:

    
    

    
    



    

        
a
        
b
        
c
        
d
    
    
e
    
f

    

The output result is as follows:

$('.test :hidden').length:4
$('.test:hidden').length:3
 DIV:a
 DIV:b
 DIV:c
 DIV:d

 DIV:d
 DIV:e
 DIV:f