tf1.x和tf2.x查看TFRecord数据的方法

Tensorflow 1.x和Tensorflow 2.x读取tfrecord方法略有不同，下面分别记录两段代码：

Tensorflow 1.x：

for example in tf.python_io.tf_record_iterator(path):
    # print(tf.train.Example.FromString(example))
    jsonMessage = MessageToJson(tf.train.Example.FromString(example))

Tensorflow 2.x：

import tensorflow as tf
import json
from google.protobuf.json_format import MessageToJson

dataset = tf.data.TFRecordDataset("mydata.tfrecord")
for d in dataset:
    ex = tf.train.Example()
    ex.ParseFromString(d.numpy())
    m = json.loads(MessageToJson(ex))
    print(m['features']['feature'].keys())