1.arr.toSring() => 數(shù)組轉(zhuǎn)為字符串
var arr = [1,2,3];
arr.toSring();
// arr => “1,2,3”
2.arr.join("-") = > 數(shù)組以分隔符轉(zhuǎn)為字符串
var arr = [1,2,3];
arr.join("+");
//arr =>? "1+2+3"
3.arr.pop() => 刪除數(shù)組中最后一個(gè)元素(返回已刪除的元素)
var arr = [1,2,3];
var last = arr.pop();
// last => 3
// arr => [1,2]
4.arr.push("lastValue")? => 向數(shù)組末尾添加一個(gè)新元素(返回新數(shù)組的長度)
var arr = [1,2];
var length = arr.push(3);
//arr => [1,2,3]
//length => 3
5.arr.shift() => 刪除數(shù)組中的首個(gè)元素(返回已刪除的元素）
var arr = [1,2,3];
var first = arr.shift();
//arr => [2,3]
//first => 1
6.arr.unshift("fistValue") => 在數(shù)組開頭添加一個(gè)新元素(返回新數(shù)組的長度)
var arr = [1,2,3];
var length = arr.unshift(0);
//arr? => [0,1,2,3]
//length => 4
7.arr[arr.length] = "lastValue" 通過索引(下標(biāo))訪問/修改數(shù)組
var arr = [0,1,2,3];
var first = arr[0];
arr[3] = 4;
arr[arr.length]? = "last"
//fist => 0
//arr[3] => 4
//arr => [0,1,2,4]
//arr = > [0,1,2,4,"last"]
8.?delete arr[index] => 根據(jù)數(shù)組下標(biāo)刪除元素(返回true)
var arr = [0,1,2,4,"last"];
var? empty? = delete arr[3];
//empty => true
//arr => [0,1,2,empty,"last"]
9.splice(index,deleteNum,addValue)? ?=> 根據(jù)下標(biāo)添加/刪除數(shù)組(返回已刪除的)
addValue : 添加新元素瞪讼，可省略
var arr = [1,2,3]
var delete = arr.splice(1,1,"last");? ?
//從數(shù)組下標(biāo)為1開始刪除1個(gè)，添加"last"
//delete =>? [2]
//arr => [1,"last",3]
10.newArr = arr3.concat(arr1,arr2) => 合并/連接數(shù)組(不更改原數(shù)組绩郎，返回新數(shù)組)
arr1 = [1,2,3];
arr2 = [4,5,6]
arr3 = [7,8,9];
newArr = arr3.concat(arr1,arr2,[1,2]);
//newArr? => [7,8,9,1,2,3,4,5,6,1,2]
11.var cutDate = slice(start,end) =>? 返回選取下標(biāo)之間的新數(shù)組，不包含end下標(biāo)元素溉跃，不修改原數(shù)組,可省略end參數(shù)啸澡，默認(rèn)選取到最后。
arr1 = [1,2,3];
sliceData = [1];
//sliceDate => 1
12.sort() => 以字母由a-z/數(shù)字由0到9順序?qū)?shù)組進(jìn)行排序
arr = [1,3,2];
arr.sort();
//arr => [1,2,3]
arr1 = ["g","e","a"];
arr1.sort();
//arr1 => ["a","e","g"]
如果數(shù)字按照字符串來排序堤器，則 "25" 大于 "100"泉蝌，因?yàn)?"2" 大于 "1"歇万。
可{比值函數(shù)}來修正此問題：
//原理
當(dāng)?sort()?函數(shù)比較兩個(gè)值時(shí)揩晴，會將值發(fā)送到比較函數(shù)，并根據(jù)所返回的值（負(fù)贪磺、零或正值）對這些值進(jìn)行排序硫兰。?
//升序
var points = [40, 100, 1, 5, 25, 10];
points.sort(function(a, b){return a - b});
//如果返回負(fù)值則把a(bǔ)排在b前面
// points[0] => 最低值
// points[points.length-1] => 最高值
//降序
var points = [40, 100, 1, 5, 25, 10];
points.sort(function(a, b){return b - a});
//如果返回負(fù)值則把a(bǔ)排在b前面?
// points[0] => 最高值?
//?points[points.length-1] => 最低值
//以隨機(jī)順序排序數(shù)組
var points = [40, 100, 1, 5, 25, 10];
points.sort(function(a, b){return 0.5 - Math.random()});
13.reverse() =>?反轉(zhuǎn)數(shù)組中的元素
arr = [1,3,2];
arr.reverse ();? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ??
//arr=> [2,3,1];
arr.reverse();
//arr => [1,3,2]
14.查找數(shù)組中的最高/最小值
max = Math.max.apply(null,arr)
min = Math.min.apply(null,arr)
