JSON.parse无法从字符串创建对象

Question

I am using ruby on rails to create a cookie that returns an array containing the params of the request back to the view as a string. However, I get the following error when I JSON.parse that string:

JSON.parse('%7B%22specialty%22%3A%5B%22Anesthesiology%22%5D%7D')

Uncaught SyntaxError: Unexpected token % in JSON at position 0

how do I fix this?

Answer 1

The string is not valid json.

It is uri encoded so decode it using decodeURIComponent()

JSON.parse(decodeURIComponent('%7B%22specialty%22%3A%5B%22Anesthesiology%22%5D%7D'))

Answer 2

You need to use decodeURIComponent to first decode the string.

JSON.parse(decodeURIComponent(
  '%7B%22specialty%22%3A%5B%22Anesthesiology%22%5D%7D'
));

As the string is encoded. Once you decode it, you get the key value pair, ie the object in the form of a string. Now you can use JSON.parse to form the Javascript object.

Answer 3

Other answers are correct in saying that the payload is URI encoded, but decodeURIComponent is only a javascript method. To decode it ruby-side, use URI.unescape .

JSON.parse(URI.unescape('%7B%22specialty%22%3A%5B%22Anesthesiology%22%5D%7D'))

You say you're using rails, so the URI object should already be available, but if you weren't using rails you would need to require 'uri' first.