获取图片真实尺寸
根据图片地址,获取该图片的实际宽度和高度
let img = new Image()
img.src = 'https://www.baidu.com/img/bd_logo1.png?qua=high'
img.onload = function() {
let nWidth = img.naturalWidth;
let nHeight = img.naturalHeight;
console.log(nWidth, nHeight)
}
文件转成二进制
使用input['file']
等获取的文件DataURI,将其转成二进制数据
function convertDataURIToBinary(dataURI) {
var BASE64_MARKER = ';base64,';
var base64Index = dataURI.indexOf(BASE64_MARKER) + BASE64_MARKER.length;
var base64 = dataURI.substring(base64Index);
var raw = window.atob(base64);
var rawLength = raw.length;
var array = new Uint8Array(new ArrayBuffer(rawLength));
for (let i = 0; i < rawLength; i++) {
array[i] = raw.charCodeAt(i);
}
return array;
}
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