将图片base64格式转换为file对象并读取(两种方式读取)

两种方式读取,一种URL.createObjectURL,另一种fileReader
 
var base64 = `
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`
var bytes=window.atob(base64.split(',')[1]); //去掉url的头,并转换为byte
//处理异常,将ascii码小于0的转换为大于0
var ab = new ArrayBuffer(bytes.length);
var ia = new Uint8Array(ab);
for (var i = 0; i < bytes.length; i++) {
ia[i] = bytes.charCodeAt(i);
}
let file = new File([ia],{
type: 'image/png',
});
// var base = URL.createObjectURL(file);ok!!!
var fr = new FileReader();
fr.onload = function(e){
var base = this.result;
var imgBase64 = document.querySelector("#imgBase64");
imgBase64.setAttribute("src",base);
}
fr.readAsDataURL(file);
 
原文地址:https://www.cnblogs.com/iroading/p/11097950.html