简体中文（ZH-CN）English（EN）繁体中文（ZH-TW）日本語（JA）한국어（KO）Melayu（MS）Français（FR）Deutsch（DE）
Home
Article
Q&A
Course
Topic
Download
Game
Dictionary
Recent Updates

Home  >  Article  >  Web Front-end  >  A collection of jquery methods for traversing and filtering arrays and json objects

A collection of jquery methods for traversing and filtering arrays and json objects

php中世界最好的语言
php中世界最好的语言Original
2018-04-24 14:36:462516browse

This time I bring you a collection of methods for jquery to traverse and filter arrays and json objects. What are the precautions for jquery to traverse and filter arrays and json objects? The following is a practical case, let's take a look.

jquery grep() filter

Traverse the array 

$().ready( 
function(){ 
var array = [1,2,3,4,5,6,7,8,9]; 
var filterarray = $.grep(array,function(value){ 
return value > 5;//筛选出大于5的 
}); 
for(var i=0;i<filterarray.length;i++){ 
alert(filterarray[i]); 
} 
for (key in filterarray){ 
alert(filterarray[key]); 
} 
} 
);

jquery each() filter the traverse array

$().ready( 
function(){ 
var anObject = {one:1,two:2,three:3};//对json数组each 
$.each(anObject,function(name,value) { 
alert(name); 
alert(value); 
}); 
var anArray = [&#39;one&#39;,&#39;two&#39;,&#39;three&#39;]; 
$.each(anArray,function(n,value){ 
alert(n); 
alert(value); 
} 
); 
} 
);

jquery inArray() filter the traverse array

$().ready( 
function(){ 
var anArray = [&#39;one&#39;,&#39;two&#39;,&#39;three&#39;]; 
var index = $.inArray(‘two&#39;,anArray); 
alert(index);//返回该值在数组中的键值，返回1 
alert(anArray[index]);//value is two 
} 
);

jquery map() filters and traverses the array

$().ready( 
function(){ 
var strings = [&#39;0&#39;,&#39;1&#39;,&#39;2&#39;,&#39;3&#39;,&#39;4&#39;,&#39;S&#39;,&#39;6&#39;]; 
var values = $.map(strings,function(value){ 
var result = new Number(value); 
return isNaN(result) ? null:result;//isNaN:is Not a Number的缩写 
} 
); 
for (key in values) { 
alert(values[key]); 
} 
} 
);

js traverses and parses json object 1

var json = [{dd:&#39;SB&#39;,AA:&#39;东东&#39;,re1:123},{cccc:&#39;dd&#39;,lk:&#39;1qw&#39;}]; 
for(var i=0,l=json.length;i<l;i++){ 
for(var key in json[i]){ 
alert(key+&#39;:&#39;+json[i][key]); 
} 
}

js traverses and parses json object 2

There are the following json objects: 

var obj ={”name”:”冯娟”,”password”:”123456″,”department”:”技术部”,”sex”:” 女”,”old”:30}; 遍历方法： 
for(var p in obj){ str = str+obj[p]+&#39;,&#39;; return str; }

The following is an example to illustrate the specific implementation method

How JQuery gets the object

$(‘#id&#39;) ：通过元素的id 
$(‘tagName&#39;) : 通过元素的标签名 
$(‘tagName tagName&#39;) : 通过元素的标签名,eg: $(‘ul li&#39;) 
$(‘tagName#id): 通过元素的id和标签名 
$(‘:checkbox&#39;):拿取input的 type为checkbox&#39;的所有元素: 
Eg: <input type="checkbox" name="appetizers" 
value="imperial"/> 
$('span[price] input[type=text]') ：拿取下面的input元素 
<span price="3"> 
<input type="text" name="imperial.quantity" 
disabled="disabled" value="1"/> 
</span> 
$('p',$(this).parents('p:first'))：拿取该p的上（至少都是父节点）的第一个p节点 
$('~ span:first',this)： locates the first sibling of this that's a <span> element.
Lazy loading of js files:

$.getScript
Example:
Html file:

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"> 
<html> 
<head> 
<title>$.getScript Example</title> 
<link rel="stylesheet" type="text/css" href="../common.css"> 
<script type="text/javascript" 
src="../scripts/jquery-1.2.1.js"></script> 
<script type="text/javascript"> 
$(function(){ 
$('#loadButton').click(function(){ 
$.getScript(//在Firefox/3.0.1中会出现一个错误(语法错误,定义的变量不起作用,ff2没问题) 
'new.stuff.js'//,function(){$('#inspectButton').click()} 
); 
}); 
$('#inspectButton').click(function(){ 
someFunction(someVariable); 
test() 
}); 
}); 
</script> 
</head> 
<body> 
<button type="button" id="loadButton">Load</button> 
<button type="button" id="inspectButton">Inspect</button> 
</body> 
</html> 
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"> 
<html> 
<head> 
<title>$.getScript Example</title> 
<link rel="stylesheet" type="text/css" href="../common.css"> 
<script type="text/javascript" 
src="../scripts/jquery-1.2.1.js"></script> 
<script type="text/javascript"> 
$(function(){ 
$('#loadButton').click(function(){ 
$.getScript(//在Firefox/3.0.1中会出现一个错误(语法错误,定义的变量不起作用,ff2没问题) 
'new.stuff.js'//,function(){$('#inspectButton').click()} 
); 
}); 
$('#inspectButton').click(function(){ 
someFunction(someVariable); 
test() 
}); 
}); 
</script> 
</head> 
<body> 
<button type="button" id="loadButton">Load</button> 
<button type="button" id="inspectButton">Inspect</button> 
</body> 
</html>
Js file: 

alert("I'm inline!"); 
var someVariable = 'Value of someVariable'; 
function someFunction(value) { 
alert(value); 
} 
function test() { 
alert('test'); 
} 
alert("I'm inline!"); 
var someVariable = 'Value of someVariable'; 
function someFunction(value) { 
alert(value); 
} 
function test() { 
alert('test'); 
}
jquery array processing: 

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"> 
<html> 
<head> 
<title>Hi!</title> 
<script type="text/javascript" src="../scripts/jquery-1.2.1.js"> 
</script> 
<script type="text/javascript"> 
var $ = 'Hi!'; 
jQuery(function(){ 
alert('$ = '+ $);//这里的 $ 为 Hi!,把它变回jquery的符号:jQuery(function($){...}/这样就可以了 
//alert(jQuery) 
}); 
jQuery(function($){ 
//------------遍历数组 .each的使用------------- 
var anArray = ['one','two','three']; 
$.each(anArray,function(n,value) { 
//do something here 
//alert(n+' '+value); 
}); 
var anObject = {one:1, two:2, three:3}; 
$.each(anObject,function(name,value) { 
//do something here 
//alert(name+' '+value); 
}); 
//-----------过滤数组 .grep的使用------------ 
var originalArray =[99,101,103]; 
var bigNumbers = $.grep(originalArray,'a>100');//第2种写法,还可以用正则表达式来过滤 
$.each(bigNumbers,function(n,value) { 
//do something here 
//alert(n+' '+value); 
}); 
//------------转换数组 .map的使用------------ 
var strings = ['1','2','3','4','S','K','6']; 
var values = $.map(strings,function(value){ 
var result = new Number(value); 
return isNaN(result) ? null : result;//如果result不是数字则 返回null（返回null在这里相当于不返回） 
}); 
$.each(values,function(n,value) { 
//do something here 
//alert(value); 
}); 
var characters = $.map( 
['this','that','other thing'], 
function(value){return value.split('');}//分离字符串用返回给characters 
); 
//alert(characters.length); 
//------------.inArray(value,array)的使用------------返回value在array下标的位置，如果value不在array中则返回-1 
var index = $.inArray(2,[1,2,3,4,5]); 
//alert(index); 
//------------makeArray(obj)的使用------------将类数组对象转换为数组对象。 
var arr = jQuery.makeArray(document.getElementsByTagName_r("p")); 
//arr.reverse(); // 使用数组翻转函数 
$.each(arr,function(n,value) { 
//do something here 
//alert(n+' '+value); 
//alert(value.html()); 
}); 
var arr2 =$.unique(document.getElementsByTagName_r("p")); //获得唯一的对象，看API,说得很模 
糊,http://docs.jquery.com/Utilities/jQuery.unique 
alert(); 
$.each(arr2,function(n,value) { 
//do something here 
alert(n+' '+value); 
}); 
}); 
</script> 
</head> 
<body> 
<p>First</p><p>Second</p><p>Third</p><p>Fourth</p><p>Fourth</p> 
</body> 
</html> 
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"> 
<html> 
<head> 
<title>Hi!</title> 
<script type="text/javascript" src="../scripts/jquery-1.2.1.js"> 
</script> 
<script type="text/javascript"> 
var $ = 'Hi!'; 
jQuery(function(){ 
alert('$ = '+ $);//这里的 $ 为 Hi!,把它变回jquery的符号:jQuery(function($){...}/这样就可以了 
//alert(jQuery) 
}); 
jQuery(function($){ 
//------------遍历数组 .each的使用------------- 
var anArray = ['one','two','three']; 
$.each(anArray,function(n,value) { 
//do something here 
//alert(n+' '+value); 
}); 
var anObject = {one:1, two:2, three:3}; 
$.each(anObject,function(name,value) { 
//do something here 
//alert(name+' '+value); 
}); 
//-----------过滤数组 .grep的使用------------ 
var originalArray =[99,101,103]; 
var bigNumbers = $.grep(originalArray,'a>100');//第2种写法,还可以用正则表达式来过滤 
$.each(bigNumbers,function(n,value) { 
//do something here 
//alert(n+' '+value); 
}); 
//------------转换数组 .map的使用------------ 
var strings = ['1','2','3','4','S','K','6']; 
var values = $.map(strings,function(value){ 
var result = new Number(value); 
return isNaN(result) ? null : result;//如果result不是数字则 返回null（返回null在这里相当于不返回） 
}); 
$.each(values,function(n,value) { 
//do something here 
//alert(value); 
}); 
var characters = $.map( 
['this','that','other thing'], 
function(value){return value.split('');}//分离字符串用返回给characters 
); 
//alert(characters.length); 
//------------.inArray(value,array)的使用------------返回value在array下标的位置，如果value不在array中则返回 
-1 
var index = $.inArray(2,[1,2,3,4,5]); 
//alert(index); 
//------------makeArray(obj)的使用------------将类数组对象转换为数组对象。 
var arr = jQuery.makeArray(document.getElementsByTagName_r("p")); 
//arr.reverse(); // 使用数组翻转函数 
$.each(arr,function(n,value) { 
//do something here 
//alert(n+' '+value); 
//alert(value.html()); 
}); 
var arr2 =$.unique(document.getElementsByTagName_r("p")); //获得唯一的对象，看API,说得很模 
糊,http://docs.jquery.com/Utilities/jQuery.unique 
alert(); 
$.each(arr2,function(n,value) { 
//do something here 
alert(n+' '+value); 
}); 
}); 
</script> 
</head> 
<body> 
<p>First</p><p>Second</p><p>Third</p><p>Fourth</p><p>Fourth</p> 
</body> 
</html>
I believe you have mastered the method after reading the case in this article. For more exciting information, please pay attention to other related articles on the PHP Chinese website!

Recommended reading:

Detailed explanation of the steps for jquery to remove selected values ​​from an array

The jQuery plug-in implements interlaced table color changing and mouse events Realize interaction

The above is the detailed content of A collection of jquery methods for traversing and filtering arrays and json objects. For more information, please follow other related articles on the PHP Chinese website!

Statement：
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
Previous article：Detailed explanation of steps to remove selected value from array using jqueryNext article：Detailed explanation of steps to remove selected value from array using jquery

Related articles

See more