javascript - 使用 JavaScript 将 ID 添加到 Canvas

Question

我正在尝试使用 JavaScript 将 ID 添加到 Canvas ，但我正在尝试修改以下特定代码。请注意，我只是假设这是我设置属性的地方。为任何帮助干杯。

THREE.CanvasRenderer = function ( parameters ) {

console.log( 'THREE.CanvasRenderer', THREE.REVISION );

parameters = parameters || {};

var _this = this,
    _renderData, _elements, _lights,
    _projector = new THREE.Projector(),

    _canvas = parameters.canvas !== undefined
             ? parameters.canvas
             : document.createElement( 'canvas' ),

    _canvasWidth = _canvas.width,
    _canvasHeight = _canvas.height,
    _canvasWidthHalf = Math.floor( _canvasWidth / 2 ),
    _canvasHeightHalf = Math.floor( _canvasHeight / 2 ),

    _viewportX = 0,
    _viewportY = 0,
    _viewportWidth = _canvasWidth,
    _viewportHeight = _canvasHeight,

    _pixelRatio = 1,

    _context = _canvas.getContext( '2d', {
        alpha: parameters.alpha === true
    } ),

Answer 1

您可以直接设置id属性:

_canvas.id = 'whatever';

编辑

上面的代码应该可以工作，但它需要在您拥有的大变量初始化 block 之后:

// start var initialization
var _this = this,
    _renderData, _elements, _lights,
    _projector = new THREE.Projector(),

    _canvas = parameters.canvas !== undefined
             ? parameters.canvas
             : document.createElement( 'canvas' ),

    _canvasWidth = _canvas.width,
    _canvasHeight = _canvas.height,
    _canvasWidthHalf = Math.floor( _canvasWidth / 2 ),
    _canvasHeightHalf = Math.floor( _canvasHeight / 2 ),

    _viewportX = 0,
    _viewportY = 0,
    _viewportWidth = _canvasWidth,
    _viewportHeight = _canvasHeight,

    _pixelRatio = 1,

    _context = _canvas.getContext( '2d', {
        alpha: parameters.alpha === true
    } ),

    ... more code,

    theEnd = true;
// end var initialization

_canvas.id = 'whatever';

^ 这整件事是一个大的 var 初始化。在某个时刻它会结束并且可能会有一个分号。您将在此处添加 ID 代码。

我认为您遇到了意外的标记错误，因为您试图在 var 初始化中的逗号之间添加一些代码。