判斷圖片加載完成
const imgLoadAll = function (arr, callback) { //圖片加載
let arrImg = []
for (let i = 0; i < arr.length; i++) {
let img = new Image()
img.src = arr[i]
img.onload = function() {
arrImg.push(this)
if(arrImg.length === arr.length) {
callback && callback()
}
}
}
}
音頻完成加載操作
const loadAudio = function(src, callback) {
let audio = new Audio(src)
audio.onloadedmetadata = callback
audio.src = src
}
瀏覽器是否支持Webp格式
const isSupportWebp = function () {
return !![].map &&
document.createElement('canvas').toDataURL('image/webp').indexOf('data:image/webp') == 0;
}