Python学习笔记之解析json的方法分析

> import json
> json.dumps(['foo', {'bar': ('baz', None, 1.0, 2)}])
'["foo", {"bar": ["baz", null, 1.0, 2]}]'
> print json.dumps("\"foo\bar")
"\"foo\bar"
> print json.dumps(u'\u1234')
"\u1234"
> print json.dumps('\\')
"\\"
> print json.dumps({"c": 0, "b": 0, "a": 0}, sort_keys=True)
{"a": 0, "b": 0, "c": 0}
> from StringIO import StringIO
> io = StringIO()
> json.dump(['streaming API'], io)
> io.getvalue()
'["streaming API"]'

> import json
> json.dumps([1,2,3,{'4': 5, '6': 7}], sort_keys=True, separators=(',',':'))
'[1,2,3,{"4":5,"6":7}]'
Pretty printing::
> import json
> print json.dumps({'4': 5, '6': 7}, sort_keys=True,
         indent=4, separators=(',', ': '))
{
  "4": 5,
  "6": 7
}

> import json
> obj = [u'foo', {u'bar': [u'baz', None, 1.0, 2]}]
> json.loads('["foo", {"bar":["baz", null, 1.0, 2]}]') == obj
True
> json.loads('"\\"foo\\bar"') == u'"foo\x08ar'
True
> from StringIO import StringIO
> io = StringIO('["streaming API"]')
> json.load(io)[0] == 'streaming API'
True

> import json
> def as_complex(dct):
   if '__complex__' in dct:
     return complex(dct['real'], dct['imag'])
   return dct
> json.loads('{"__complex__": true, "real": 1, "imag": 2}',
   object_hook=as_complex)
(1+2j)
> from decimal import Decimal
> json.loads('1.1', parse_float=Decimal) == Decimal('1.1')
True

> import json
> def encode_complex(obj):
   if isinstance(obj, complex):
     return [obj.real, obj.imag]
   raise TypeError(repr(o) + " is not JSON serializable")
> json.dumps(2 + 1j, default=encode_complex)
'[2.0, 1.0]'
> json.JSONEncoder(default=encode_complex).encode(2 + 1j)
'[2.0, 1.0]'
> ''.join(json.JSONEncoder(default=encode_complex).iterencode(2 + 1j))
'[2.0, 1.0]'