javascript数组（array）的常用方法（shift/unshift/pop/push/concat/splice/reverse/sort/slice/join）

数组array

今天简单的介绍一下array对象的常用方法（shift/unshift/pop/push/concat/splice/reverse/sort/slice/join）在这就不多说直接撸代码

1.获取数组的长度 length

2.删除数组的第一个元素 shift

3.删除数组的最后一个元素 pop

4.删除或替换数组中的值,返回删除的值 splice 

5. 在数组前添加元素,返回数组长度 unshift

6.在数组后添加元素,返回数组长度 push

7.将数组反续 reverse

8.按指定的参数排序 sort

9.连接两个或更多的数组，并返回结果 concat

10.数组截取 slice

11.将数组元素组成一个字符串   join

12.将数组转化成字符串 toString 

13.将数组转换为本地数组 toLocaleString

代码示例如下：

（实例中arr数组是一直随着每条命令修改而变化的不是固定一个值的）

<script type="text/javascript">var arr=["a","b","c","d","e","f","g","h","i","j"];// 数组的长度 length   var arrLength=arr.length;  // arrLength=10//删除数组元素 shift pop  ==>  splice(替换删除)   // shift 删除数组的第一个元素，返回删除的值      var arrShift=arr.shift();   // arr=["b","c","d","e","f","g","h","i","j"]                                  // arrShift="a"   // pop 删除数组的最后一个元素，返回删除的值      var arrPop=arr.pop();  // arr=["b","c","d","e","f","g","h","i"]                             // arrPop="j"   // splice 删除或替换数组中的值,返回删除的值  splice(开始值下标,个数,替换的值,替换的值.....)      var arrSplice=arr.splice(2,2)   // arr=["b","c","f","g","h","i"]                                     // arrSplice=["d","e"]      var arrSpliceTwo=arr.splice(0,3,"a","b","c")   // arr=["a","b","c","g","h","i"]                                                            // arrSpliceTwo=["b","c","f"]// 添加数组元素 unshift push    // 在数组前添加元素,返回数组长度      var arrUnshift=arr.unshift("1");   // arr=["1","a","b","c","g","h","i"]                                         // arrUnshift=7   // 在数组后添加元素,返回数组长度      var arrPush=arr.push("j");   // arr=["1","a","b","c","g","h","i","j"]                                   // arrPush=8// 给数组内部元素排序 reverse sort   // 将数组反续 reverse      var arrReverse=arr.reverse();   // arr=["j","i","h","g","c","b","a","1"]                                      // arrReverse=["j","i","h","g","c","b","a","1"]   // 按指定的参数排序 sort 可以传递函数进行计算      var arrSort=arr.sort();   // arr=["1","a","b","c","g","h","i","j"]                                // arrSort=["1","a","b","c","g","h","i","j"]//连接两个或更多的数组，并返回结果 concat   var arrOne=[2,3,4];   var arrTwo=[6,7,8];   var arrS=["a","b","c"];   var arrArr=arrOne.concat(arrTwo);   //arrArr=[2, 3, 4, 6, 7, 8]   var arrArrT=arrOne.concat(arrTwo,arrS);   //arrArrT=[2, 3, 4, 6, 7, 8, "a", "b", "c"]   var arrArrS=arrOne.concat("5","6","7");   //arrArrS=[2, 3, 4, "5", "6", "7"]// 数组截取 slice slice(start,end) 不包括end值   var arrSlice=arr.slice(2,5);   // arr=["1","a","b","c","g","h","i","j"]                                  // arrSlice= ["b", "c", "g"]// 数组变为字符串 join toString toLocaleString   // 将数组元素组成一个字符串  以（）中的值为分割符，默认为","      var arrJoin=arr.join("");   // arr=["1","a","b","c","g","h","i","j"]                                     // arrJoin= 1abcghij      var arrJoinTwo=arr.join();   // arrJoinTwo=1,a,b,c,g,h,i,j      var arrJoinS=arr.join("-");   // arrJoinS=1-a-b-c-g-h-i-j//将数组转化成字符串   var arrString=arr.toString();   // arr=["1","a","b","c","g","h","i","j"]                                   // arrString= 1,a,b,c,g,h,i,j//将数组转换为本地数组   var arrLocaleString=arr.toLocaleString();   // arr=["1","a","b","c","g","h","i","j"]                                               // arrString= 1,a,b,c,g,h,i,j</script>