* Loads an image for a given File object. * * @param {Blob|string} file Blob object or image URL * @param {Function|object} [callback] Image load event callback or options * @param {object} [options] Options object * @returns {HTMLImageElement|FileReader|Promise } Object
(file, callback, options)
| 100 | * @returns {HTMLImageElement|FileReader|Promise<Result>} Object |
| 101 | */ |
| 102 | function loadImage(file, callback, options) { |
| 103 | /** |
| 104 | * Promise executor |
| 105 | * |
| 106 | * @param {Function} resolve Resolution function |
| 107 | * @param {Function} reject Rejection function |
| 108 | * @returns {HTMLImageElement|FileReader} Object |
| 109 | */ |
| 110 | function executor(resolve, reject) { |
| 111 | var img = document.createElement('img') |
| 112 | var url |
| 113 | /** |
| 114 | * Callback for the fetchBlob call. |
| 115 | * |
| 116 | * @param {HTMLImageElement|HTMLCanvasElement} img Error object |
| 117 | * @param {object} data Data object |
| 118 | * @returns {undefined} Undefined |
| 119 | */ |
| 120 | function resolveWrapper(img, data) { |
| 121 | if (resolve === reject) { |
| 122 | // Not using Promises |
| 123 | if (resolve) resolve(img, data) |
| 124 | return |
| 125 | } else if (img instanceof Error) { |
| 126 | reject(img) |
| 127 | return |
| 128 | } |
| 129 | data = data || {} // eslint-disable-line no-param-reassign |
| 130 | data.image = img |
| 131 | resolve(data) |
| 132 | } |
| 133 | /** |
| 134 | * Callback for the fetchBlob call. |
| 135 | * |
| 136 | * @param {Blob} blob Blob object |
| 137 | * @param {Error} err Error object |
| 138 | */ |
| 139 | function fetchBlobCallback(blob, err) { |
| 140 | if (err && $.console) console.log(err) // eslint-disable-line no-console |
| 141 | if (blob && isInstanceOf('Blob', blob)) { |
| 142 | file = blob // eslint-disable-line no-param-reassign |
| 143 | url = createObjectURL(file) |
| 144 | } else { |
| 145 | url = file |
| 146 | if (options && options.crossOrigin) { |
| 147 | img.crossOrigin = options.crossOrigin |
| 148 | } |
| 149 | } |
| 150 | img.src = url |
| 151 | } |
| 152 | img.onerror = function (event) { |
| 153 | revokeHelper(url, options) |
| 154 | if (reject) reject.call(img, event) |
| 155 | } |
| 156 | img.onload = function () { |
| 157 | revokeHelper(url, options) |
| 158 | var data = { |
| 159 | originalWidth: img.naturalWidth || img.width, |
no test coverage detected