AttributeError(“'str' object has no attribute 'read'”)

问题

In Python I'm getting an error:

Exception:  (<type 'exceptions.AttributeError'>,
AttributeError("'str' object has no attribute 'read'",), <traceback object at 0x1543ab8>)

Given python code:

def getEntries (self, sub):
    url = 'http://www.reddit.com/'
    if (sub != ''):
        url += 'r/' + sub

    request = urllib2.Request (url + 
        '.json', None, {'User-Agent' : 'Reddit desktop client by /user/RobinJ1995/'})
    response = urllib2.urlopen (request)
    jsonofabitch = response.read ()

    return json.load (jsonofabitch)['data']['children']

What does this error mean and what did I do to cause it?

回答1:

The problem is that for json.load you should pass a file like object with a read function defined. So either you use json.load(response) or json.loads(response.read()).

回答2:

AttributeError("'str' object has no attribute 'read'",)

This means exactly what it says: something tried to find a .read attribute on the object that you gave it, and you gave it an object of type str (i.e., you gave it a string).

The error occurred here:

json.load (jsonofabitch)['data']['children']

Well, you aren't looking for read anywhere, so it must happen in the json.load function that you called (as indicated by the full traceback). That is because json.load is trying to .read the thing that you gave it, but you gave it jsonofabitch, which currently names a string (which you created by calling .read on the response).

Solution: don't call .read yourself; the function will do this, and is expecting you to give it the response directly so that it can do so.

You could also have figured this out by reading the built-in Python documentation for the function (try help(json.load), or for the entire module (try help(json)), or by checking the documentation for those functions on http://docs.python.org .

回答3:

If you get a python error like this:

AttributeError: 'str' object has no attribute 'some_method'

You probably poisoned your object accidentally by overwriting your object with a string.

How to reproduce this error in python with a few lines of code:

#!/usr/bin/env python
import json
def foobar(json):
    msg = json.loads(json)

foobar('{"batman": "yes"}')

Run it, which prints:

AttributeError: 'str' object has no attribute 'loads'

But change the name of the variablename, and it works fine:

#!/usr/bin/env python
import json
def foobar(jsonstring):
    msg = json.loads(jsonstring)

foobar('{"batman": "yes"}')

This error is caused when you tried to run a method within a string. String has a few methods, but not the one you are invoking. So stop trying to invoke a method which String does not define and start looking for where you poisoned your object.

来源：https://stackoverflow.com/questions/11174024/attributeerrorstr-object-has-no-attribute-read