如何使用JavaScript动态创建数组

Question

Im trying something which is probably very easy but i cant seem to find out why its not working. Im trying to dynamically create and array with jquery/javascript.

my code;

var icons = $('.icon');

var desktopicons = [];

var user = { name: username };

var iconsetup = { myicons: [] };

desktopicons.push(user);
desktopicons.push(iconsetup);

$.each(icons, function() {
        var name = $(this).attr('name');
    var rel = $(this).attr('rel');


    var icon = { 
        icon: [{
            name: name,
            rel: rel
        }]
    };

    iconsetup.myicons[0].push(icon);

});

desktopicons.push(user);
desktopicons.push(iconsetup);

$('#desktop').append(desktopicons[0].name);
$('#desktop').append(desktopicons[1].myicons[0].icon[0].name);

Somehow my log file says cannot call method push of undefined on 'iconsetup.myicons[0].push(icon);' this line.

Anyone who can tell me how to create the array? Thanks!

Answer 1

You are using myicons[0] which means you get the first item of the myicons and that is not an array

Use

iconsetup.myicons.push(icon);

---

You could also simplify the whole .each() section with

iconsetup.myicons = icons.map(function(idx, item){
   return {icon:[{name: item.name, rel: item.rel}]}
}).get();

Answer 2

您正在尝试将图标推myicons[0]未定义的myicons[0] ，而是需要推送到myicons，这会将图标添加到数组中：

iconsetup.myicons.push(icon);

Answer 3

You never set iconsetup.myicons[0] equal to anything. iconsetup.myicons is simply an empty array with nothing in it, and no element 0. Maybe you meant:

iconsetup.myicons.push(icon);