Buffer转字符串及base64转Blod

Buffer转字符串

function ab2str(buf) {
	return String.fromCharCode.apply(null, new Uint8Array(buf));
}

base64转Blod

function base64ToBlob(urlData) {

    var bytes = window.atob(urlData.split(',')[1]);

    //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);
    }

    return new Blob([ab], { type: 'image/jpeg', lastModified: new Date() });
}

字符串转Buffer很简单：

Buffer.from("hello","ASCII")

第二个参数可填其它类型