Can't read json file

[AustinJia]

• Describe what you want to achieve.
  Read .json file as json object

• Describe what you tried.
  downloaded the include/nlohmann folder in my local project's include folder
  Create a .json file in src
  std::ifstream i(path+"config.json", std::ifstream::binary);
json j;
i >> j;
  it always shows

[json.exception.parse_error.101] parse error at line 1, column 1: syntax error while parsing value - unexpected end of input; expected '[', '{', or a literal

• Describe which system (OS, compiler) you are using.
  ubuntu 16.04 xenial

• Describe which version of the library you are using (release version, develop branch).
  JSON for Modern c++ v3.7.0

[nlohmann]

Why do you open the file in binary mode? Can you make sure it is properly opened (eg by piping the content to cout)?

[AustinJia]

Thanks. You are right.
I opened the file with std::ifstream::in now
I even can't print out the content to cout.
Any idea?

[AustinJia]

I figured out the issue, I was read the file from the build folder instead original folder.