从函数返回数组

Question

- 由Elliot B解决.谢谢!也可以考虑其他修改.

这是结果.谢谢大家,快速回答!http://dl.dropbox.com/u/18785762/Rust/index.html

我正在用javascript编写一个游戏,并且我希望将用于匹配块ID的文件保存到地图编译器中单独的.js文件中的文件,以便我可以轻松编辑.但是,ID存储在一个数组中,我似乎无法正确使用return函数.有帮助吗？

drawmap.js:

function drawmap() {

    var images = BlockID();

    var level = [
    "ssssssssssssssssssssss",
    "sgggggggggCCCCCdddddss",
    "ssssssssss     sssssss"
    ];

    var top = 100;
    var left = 100;
    var mytop = top;
    var myleft = left;
    for (y=0; y<level.length; ++y) {
        var row = level[y];
        for (x=0; x < row.length; ++x) {
            var c = row.charAt(x);
            if(c != ' ') {
                img_create(images[c], mytop, myleft);
            }
            mytop += 13;
            myleft += 27;
        }
        mytop = top + (y+1)*13;
        myleft = left - (y+1)*27;
    }
}

mapread.js:

function BlockID() {
    var IDs = new Array();
        images['s'] = "Images/Block_01.png";
        images['g'] = "Images/Block_02.png";
        images['C'] = "Images/Block_03.png";
        images['d'] = "Images/Block_04.png";
    return IDs;
}

Answer 1

至少,改变这个:

function BlockID() {
    var IDs = new Array();
        images['s'] = "Images/Block_01.png";
        images['g'] = "Images/Block_02.png";
        images['C'] = "Images/Block_03.png";
        images['d'] = "Images/Block_04.png";
    return IDs;
}

对此:

function BlockID() {
    var IDs = new Object();
        IDs['s'] = "Images/Block_01.png";
        IDs['g'] = "Images/Block_02.png";
        IDs['C'] = "Images/Block_03.png";
        IDs['d'] = "Images/Block_04.png";
    return IDs;
}

有几点需要指出.首先,images未在原始函数中定义,因此为其分配属性值将引发错误.我们通过更改images为更正IDs.其次,你想要归还一个Object,而不是一个Array.可以为对象分配类似于关联数组或散列的属性值 - 数组不能.所以我们将声明var IDs = new Array();改为var IDs = new Object();.

在这些更改之后,您的代码将运行正常,但可以进一步简化.您可以使用简写表示法(即,对象文字属性值简写)来创建对象并立即返回它:

function BlockID() {
    return {
            "s":"Images/Block_01.png"
            ,"g":"Images/Block_02.png"
            ,"C":"Images/Block_03.png"
            ,"d":"Images/Block_04.png"
    };
}

Answer 2

您的BlockID函数使用未定义的变量images,这将导致错误.此外,您不应该使用Array此处 - JavaScripts键值映射是普通对象:

function BlockID() {
    return {
        "s": "Images/Block_01.png",
        "g": "Images/Block_02.png",
        "C": "Images/Block_03.png",
        "d": "Images/Block_04.png"
    };
}

Answer 3

整洁:

function BlockID() {
  return {
    "s":"Images/Block_01.png",
    "g":"Images/Block_02.png",
    "C":"Images/Block_03.png",
    "d":"Images/Block_04.png"
   }
}

要不就

var images = {
  "s":"Images/Block_01.png",
  "g":"Images/Block_02.png",
  "C":"Images/Block_03.png",
  "d":"Images/Block_04.png"
}