开发者

Javascript array/object syntax fail

开发者 https://www.devze.com 2023-03-07 04:06 出处:网络
Why do I get this error with this code: Uncaught SyntaxError: Unexpected token { on line 1. var cube_points = {

Why do I get this error with this code: Uncaught SyntaxError: Unexpected token { on line 1.

var cube_points = {
    {'x' : 100, 'y' : 100, 'z' : 100},
    {'x' : 100, 'y' : 100, 'z' : -100},
    {'x' : -100, 'y' : 100, 'z' : -100},
    {'x' : -100, 'y' : 100, 'z' : 100},
    {'x' : 100, 'y' : -100, 'z' : 100},
    {'x' : 100, 'y' : -100, 'z' : -100},
    {'x' : -100, 'y开发者_Python百科' : -100, 'z' : -100},
    {'x' : -100, 'y' : -100, 'z' : 100}
};


Your outer object's elements have values but no keys. If you want an array of cube points, use the square bracket to denote an array literal:

var cube_points = [
    {'x' : 100, 'y' : 100, 'z' : 100},
    {'x' : 100, 'y' : 100, 'z' : -100},
    {'x' : -100, 'y' : 100, 'z' : -100},
    {'x' : -100, 'y' : 100, 'z' : 100},
    {'x' : 100, 'y' : -100, 'z' : 100},
    {'x' : 100, 'y' : -100, 'z' : -100},
    {'x' : -100, 'y' : -100, 'z' : -100},
    {'x' : -100, 'y' : -100, 'z' : 100}
];

If you want an object, give the items a key. This could be numbers or letters or even objects:

var cube_points = {
    1: {'x' : 100, 'y' : 100, 'z' : 100},
    2: {'x' : 100, 'y' : 100, 'z' : -100},
    'q': {'x' : -100, 'y' : 100, 'z' : -100},
    'z': {'x' : -100, 'y' : 100, 'z' : 100},
    '25': {'x' : 100, 'y' : -100, 'z' : 100},
    '26': {'x' : 100, 'y' : -100, 'z' : -100},
    10: {'x' : -100, 'y' : -100, 'z' : -100},
    11: {'x' : -100, 'y' : -100, 'z' : 100}
};

Obviously, using an object necessitates some kind of orderly system of key selection. Since your points aren't easily named, you're better off using an array. But I wanted to show what object literal notation would look like.


What you have is not a valid javascript object definition. {} denotes object, so inside you should have properties, not other {}. What you need is an array which is denoted with []:

var cube_points = [
    {'x' : 100, 'y' : 100, 'z' : 100},
    {'x' : 100, 'y' : 100, 'z' : -100},
    {'x' : -100, 'y' : 100, 'z' : -100},
    {'x' : -100, 'y' : 100, 'z' : 100},
    {'x' : 100, 'y' : -100, 'z' : 100},
    {'x' : 100, 'y' : -100, 'z' : -100},
    {'x' : -100, 'y' : -100, 'z' : -100},
    {'x' : -100, 'y' : -100, 'z' : 100}
];

which you could then access like this:

cube_points[2].y
0

精彩评论

暂无评论...
验证码 换一张
取 消