const blob = new Blob([res])
const blobUrl = window.URL.createObjectURL(blob)
arrayBufferToBase64 (buffer) { var binary = '' var bytes = new Uint8Array(buffer) var len = bytes.byteLength for (var i = 0; i < len; i++) { binary += String.fromCharCode(bytes[i]) } return window.btoa(binary) },
//图片 const base64Str = 'data:image/jpeg;base64,' + this.arrayBufferToBase64(res) //pdf const base64Str = 'data:application/pdf;base64,' + this.arrayBufferToBase64(res)