jquery Array processing Rollup

I haven't written anything for a while, and I'm going to summarize the more commonly used array processing methods in jquery.

$.each (Array, [callback]) traversal, very common

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vararr = [‘javascript‘, ‘php‘, ‘java‘, ‘c++‘, ‘c#‘, ‘perl‘, ‘vb‘, ‘html‘, ‘css‘, ‘objective-c‘];$.each(arr, function(key, val) {    // firebug console    console.log(‘index in arr:‘+ key + ", corresponding value:"+ val);    // 如果想退出循环    // return false;});

$.grep (Array, callback, [invert]) filter, commonly used

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var temp = [];temp = $.grep(arr, function(val, key) {    if(val.indexOf(‘c‘) != -1)         returntrue;    // 如果[invert]参数不给或为false, $.grep只收集回调函数返回true的数组元素    // 反之[invert]参数为true, $.grep收集回调函数返回false的数组元素}, false);console.dir(temp);

$.map (Array, [callback]) does not use too much

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//1.6之前的版本只支持数组temp = $.map(arr, function(val, key) {    //返回null,返回的数组长度减1    if(val === ‘vb‘) returnnull;    returnval;});console.dir(temp);//1.6开始支持json格式的objectvarobj = {key1: ‘val1‘, key2: ‘val2‘, key3: ‘val3‘};temp = $.map(obj, function(val, key) {    returnval;});console.dir(temp);

$.inarray (val, array) determines whether in the specified array, the common

123	//返回元素在数组中的位置,0为起始位置,返回-1则未找到该元素console.log($.inArray(‘javascript‘, arr));

$.merge (first, second) merges two arrays, using frequency generally

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varfrontEnd = [‘javascript‘, ‘css‘, ‘html‘],      backEnd = [‘java‘, ‘php‘, ‘c++‘];// 这种方式会修改第一个参数, 即frontEnd数组temp = $.merge(frontEnd, backEnd);console.dir(temp);console.dir(frontEnd);// 可以用下面的方式来避免对原数组的影响// $.merge($.merge([], frontEnd), backEnd);

$.unique (array) filters repeating elements in an array, not commonly used

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//$.unique supports only DOM element arrays, removes duplicate DOM elements, and does not support other types of arrays (string or number) //get the original Dom array, not the jquery encapsulated var  divs = $ ( ' div ' //add several div-classes as DUP divs = Divs.concat ($ ( ' div.dup ' console.log (  + divs.length); divs = $.unique (divs); console.log (  < Code class= "JavaScript plain" >+ divs.length);

$.makearray (obj) to convert class array objects to arrays, not commonly used

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//首先什么是类数组对象?jQuery官网上用divs = getElementsByTag(‘div‘)来做例子//这个divs有类似数组的一些方法比如length,通过[index]方式获取元素等//然后通过$.makeArray(divs)使它转为数组,就可以用数组的其他功能//比如reverse(), pop()等

$ (DOM). ToArray () Restores the jquery collection to a DOM array, not commonly used

12	//跟makeArray一样,相当的不常用,一般情况可以忽略

jquery Array processing Rollup