python io StringIO BytesIO 向字内存符串写入数据

来源：https://ironpython-test.readthedocs.io/en/latest/library/stringio.html

像写文件一样写入内存

Python3 代码如下

from io import StringIO

output = StringIO()
output.write('First line.\n')
print >>output, 'Second line.'

# Retrieve file contents -- this will be
# 'First line.\nSecond line.\n'
contents = output.getvalue()

# Close object and discard memory buffer --
# .getvalue() will now raise an exception.
output.close()

• io.BytesIO()

注意⚠️：Python2 中的导入和使用方式

import StringIO

output = StringIO.StringIO()