數組的幾個例子 - jc535201285－IT工程師數位筆記本

文章出處

一維數組：var attr = [1,2,3,4,5,6];只有一個

二維數組：var attr = [
[1,2,3,4],
[5,6,7,8],
[10,11,12,13]
];
alert[大數組][大數組中的某個小組的數值]；
一個數組里又有數組

var attr = [
        [1,2,3,4],
        [5,6,7,8],
        [9,8,7,6]
    ];
     
    for(var i=0;i<attr.length;i++)
    {
        for(var j=0;j<attr[i].length;j++)
        {
            alert(attr[i][j]);
        }
    }

//冒泡排序

var attr = [9,8,7,6,5,4,3,2,1];
var zj=0;
     
    //控制比較輪數
    for( var i=0;i<attr.length-1;i++)
        {
        //控制次數
        for(var j=0;j<attr.length-1-i;j++)
        {
            if(attr[j]>attr[j+1])
            {
                zj=attr[j];
                attr[j]=attr[j+1];
                attr[j+1]=zj;
            }
        }
     }
    alert(attr[0]); 

//查找某個值在數組中的位置

var attr = [1,4,5,3,2,7,6,9];
     
    var zhao = 8;
     
    var sy = -1;
     
    for(var i=0;i<attr.length;i++)
    {
        if(attr[i]==zhao)
        {
            sy = i;
        }
    }
     
    if(sy==-1)
    {
        alert("沒有找到值");
    }
    else
    {
        alert("該元素在"+sy);
    }

//幾個變量在數組中出現的次數

var attr = [1,4,3,5,6,7,8,9,0,3,4,5,6,7,8,9,2,3,5,7,6,8,0,2,2,3,8];
     
    var c3=0;
    var c5=0;
    var c7=0;
    var  a=0;
    for(var i=0;i<attr.length;i++)
    {
        switch(attr[i])
        {
            case 3:
                  c3++;
                  break;
             
            case 5:
                  c5++;
                  break;
             
            case 7:
                  c7++;
                  break;
            default:
                  a++;
             
        }
    }
    alert(attr[c3]);
    alert(attr[c5]);
    alert(attr[c7]);