JavaScript教程-配列

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1,Aray定義配列/取得
1,var arr = new Array(); //          arr         
  arr[0] = "tom";          
  arr[1] = "jim";          
  arr[2] = "   ";  

2,var a = new Array("tom", "jim", "   ") 

3,var str = [tom, jim,    ]; 
str[0] //tom
str[1]  /jim
str[2]  /   
2,Aray配列長さ
var str = [1, 2, 3, 4, 5, 6, 7, 8, 9];
var length = str.length //9
     for if           value
for( var i = 0;i
3,Aray配列は特別です.
  instanceof  =>     // return true/false
var a = [ 1,2 ]
typeof a //object;
a instanceof Array //true
a instanceof String //false

4,Aray配列方法
concat()           //          ,     。
join()                 //               。              。
pop()                  //              
push()                //               ,       。
reverse()             //          。
shift()                //             
slice()                 //               
sort()                   //          
splice()                //    ,         。
toSource()            //         。
toString()            //         ,     。
toLocaleString()  //          ,     。
unshift()          //               ,       。
valueOf()        //          
実例
js      ( )

#shift:        ,         ;         undefined

var a = [1,2,3,4,5];

var b = a.shift(); //a:[2,3,4,5] b:1

#unshift:           ,        

var a = [1,2,3,4,5];

var b = a.unshift(-2,-1); //a:[-2,-1,1,2,3,4,5] b:7

 : IE6.0        undefined,FF2.0       7,             ,         splice        。

#pop:         ,         ;         undefined

var a = [1,2,3,4,5];

var b = a.pop(); //a:[1,2,3,4] b:5

#push:           ,        

var a = [1,2,3,4,5];

var b = a.push(6,7); //a:[1,2,3,4,5,6,7] b:7

#concat:       ,              

var a = [1,2,3,4,5];

var b = a.concat(6,7); //a:[1,2,3,4,5] b:[1,2,3,4,5,6,7]

#splice(start,deleteCount,val1,val2,...): start      deleteCount ,        val1,val2,...

var a = [1,2,3,4,5];

var b = a.splice(2,2,7,8,9); //a:[1,2,7,8,9,5] b:[3,4]

var b = a.splice(0,1); // shift

a.splice(0,0,-2,-1); var b = a.length; // unshift

var b = a.splice(a.length-1,1); // pop

a.splice(a.length,0,6,7); var b = a.length; // push

#reverse:     

var a = [1,2,3,4,5];

var b = a.reverse(); //a:[5,4,3,2,1] b:[5,4,3,2,1]

#sort(orderfunction):             

var a = [1,2,3,4,5];

var b = a.sort(); //a:[1,2,3,4,5] b:[1,2,3,4,5]

#slice(start,end):                            

var a = [1,2,3,4,5];

var b = a.slice(2,5); //a:[1,2,3,4,5] b:[3,4,5]

#join(separator):             , separator    ,               

var a = [1,2,3,4,5];

var b = a.join("|"); //a:[1,2,3,4,5] b:"1|2|3|4|5"

   JavaScript         ,         ,      (push)、  (shift)    ,       for         ,         JavaScript          ?

    JavaScript     ,                  。  Object      JS        。      Array Object   :

  Array:

#  :var ary = new Array();   var ary = [];

#  :ary.push(value);

#  :delete ary[n];

#  :for ( var i=0 ; i < ary.length ; ++i ) ary[i];

#  :var obj = new Object();   var obj = {};

#  :obj[key] = value; (key string)

#  :delete obj[key];

#  :for ( var key in obj ) obj[key];

            Object             ,   Popup   

    Web   (3)     Eric     __MenuCache__,             。

        Array          ,          :