关于javascript:Util-前端-Base64-转化为-File-格式

export function base64ToFile(base64Str) {    //将base64转换为blob    const dataURLtoBlob = function(dataurl) {         var arr = dataurl.split(','),            mime = arr[0].match(/:(.*?);/)[1],            bstr = atob(arr[1]),            n = bstr.length,            u8arr = new Uint8Array(n);        while (n--) {            u8arr[n] = bstr.charCodeAt(n);        }        return new Blob([u8arr], { type: mime });    }    //将blob转换为file    const blobToFile = function(theBlob, fileName){        theBlob.lastModifiedDate = new Date();        theBlob.name = fileName;        return new window.File(            [theBlob],            theBlob.name,            { type: theBlob.type }        );    }    //调用    var blob = dataURLtoBlob(base64Str);    var file = blobToFile(blob, Math.random().toString(36).substr(2));    return file}