error C2679: binary '>>' : no operator found which takes a right-hand operand of type 'std::string' (or there is no acceptable conversion)

c++ visual-c++ compiler-errors cygwin

94,861

Solution 1

Have you included all of the following headers?

<fstream>
<istream>
<iostream>
<string>

My guess is you forgot <string>.

On a side note: That should be std::cout and std::endl.

Solution 2

Adding to @sbi answer, in my case the difference was including <string> instead of <string.h> (under VS 2017).

See the following answer: similar case answer

Solution 3

In addition to what others said. The following code was necessary in my application to compile succesfully.

std::cout << s.c_str() << std::endl;

Another work-around to this is go to project properties -> General -> Character Set and choose "Ues Multi-Byte Character Set" (You won't need to use c_str() to output the string)

There's disadvantages to using MBCS so if you plan to localize your software, I'd advize against this.

94,861

Author by

asyncwait

Updated on October 25, 2020

Comments

asyncwait over 3 years
Please don't confuse with the title as it was already asked by someone but for a different context

The below code in Visual C++ Compiler (VS2008) does not get compiled, instead it throws this exception:
```
std::ifstream input (fileName);   

while (input) {
  string s;
  input >> s;
  std::cout << s << std::endl;
};
```
But this code compiles fine in cygwin g++. Any thoughts?
asyncwait over 14 years

You're right .. I missed <string>, don't you think this error message is totally misleading. I can't relate this error message with the fix you're mentioned. Very strange!!
sbi over 14 years

@Vadi: Very likely std::string is defined in some other header you already included, but the operator is not. So the compiler accepts string s;, but not the invocation of the stream operator.
Bran van der Meer about 10 years

You dont have to specify std::cout. If you're running with using namespace std;, then just cout is enough.
sbi about 10 years

@BranvanderMeer: Why is “using namespace std;” considered bad practice?
Tahlil almost 10 years

@sbi, do you mean by defined that in some header someone did something like typedef someType string; ?
Robert Lucian Chiriac almost 10 years

Mine did show the same error. I found out that I was using the <cstring>. When I switched to simply <string> it worked.
sbi almost 10 years

@Robert Understandably so. <cstring> is the C standard library's string handling functions.
Tahlil almost 10 years

@sbi, I don't have that kind of purpose. I had the same problem too yesterday. I just wanted to know what do you mean when you said very likely std::string is defined in some other header you already included in your comment. I am a beginner in C/C++. So pardon me if it's a very silly question or the answer is too obvious. Thank you.
sbi almost 10 years

@Tahlil: The C++ standard does not specify which other headers a standard library header might or might not include, so vendors are free to do anything they want. (Since including lots of stuff is costly in terms of compilation time, sometimes they split headers into different parts that are included from different headers.) So it might happen that something you did not include is defined or declared in some header included internally. Does that answer your question?
Tahlil almost 10 years

Yes. I understand now. Thank you very much for the explanation :-)
Abhishek Goel almost 10 years

perfect. you saved me. :)
Lightness Races in Orbit over 5 years

How does this answer differ from the accepted one posted nine years ago? Okay, it's more thorough. If that's your intention then great!
Lightness Races in Orbit over 5 years

Although this doesn't really have anything to do with compilers or settings, but with how the standard library impl is laid out
Stephen.W over 2 years

got me too. What a crappy compiler error prompt! :-(