一个很疑惑的问题。

[wang7890]

我用的是 VS2005
写了个小程序，代码如下：

#include <iostream>

using namespace std;

int main()
{
string str = "hello";

cout<<str<<endl;

return 0;
}

报如下错误，
------ Build started: Project: Test, Configuration: Debug Win32 ------
Compiling...
test.cpp
c:\documents and settings\zj\desktop\aa\test\test\test.cpp(9) : error C2679: binary '<<' : no operator found which takes a right-hand operand of type 'std::string' (or there is no acceptable conversion)
c:\program files\microsoft visual studio 8\vc\include\ostream(650): could be 'std::basic_ostream<_Elem,_Traits> &std::operator <<<char,std::char_traits<char>>(std::basic_ostream<_Elem,_Traits> &,const char *)'
with
[
_Elem=char,
_Traits=std::char_traits<char>
]
c:\program files\microsoft visual studio 8\vc\include\ostream(697): or 'std::basic_ostream<_Elem,_Traits> &std::operator <<<char,std::char_traits<char>>(std::basic_ostream<_Elem,_Traits> &,char)'
with
[
_Elem=char,
_Traits=std::char_traits<char>
]
c:\program files\microsoft visual studio 8\vc\include\ostream(735): or 'std::basic_ostream<_Elem,_Traits> &std::operator <<<std::char_traits<char>>(std::basic_ostream<_Elem,_Traits> &,const char *)'
with
[
_Elem=char,
_Traits=std::char_traits<char>
]
c:\program files\microsoft visual studio 8\vc\include\ostream(782): or 'std::basic_ostream<_Elem,_Traits> &std::operator <<<std::char_traits<char>>(std::basic_ostream<_Elem,_Traits> &,char)'
with
[
_Elem=char,
_Traits=std::char_traits<char>
]
c:\program files\microsoft visual studio 8\vc\include\ostream(906): or 'std::basic_ostream<_Elem,_Traits> &std::operator <<<std::char_traits<char>>(std::basic_ostream<_Elem,_Traits> &,const signed char *)'
with
[
_Elem=char,
_Traits=std::char_traits<char>
]
c:\program files\microsoft visual studio 8\vc\include\ostream(913): or 'std::basic_ostream<_Elem,_Traits> &std::operator <<<std::char_traits<char>>(std::basic_ostream<_Elem,_Traits> &,signed char)'
with
[
_Elem=char,
_Traits=std::char_traits<char>
]
c:\program files\microsoft visual studio 8\vc\include\ostream(920): or 'std::basic_ostream<_Elem,_Traits> &std::operator <<<std::char_traits<char>>(std::basic_ostream<_Elem,_Traits> &,const unsigned char *)'
with
[
_Elem=char,
_Traits=std::char_traits<char>
]
c:\program files\microsoft visual studio 8\vc\include\ostream(927): or 'std::basic_ostream<_Elem,_Traits> &std::operator

[wang7890]

<<<std::char_traits<char>>(std::basic_ostream<_Elem,_Traits> &,unsigned char)'
with
[
_Elem=char,
_Traits=std::char_traits<char>
]
c:\program files\microsoft visual studio 8\vc\include\ostream(168): or 'std::basic_ostream<_Elem,_Traits> &std::basic_ostream<_Elem,_Traits>::operator <<(std::basic_ostream<_Elem,_Traits> &(__cdecl *)(std::basic_ostream<_Elem,_Traits> &))'
with
[
_Elem=char,
_Traits=std::char_traits<char>
]
c:\program files\microsoft visual studio 8\vc\include\ostream(174): or 'std::basic_ostream<_Elem,_Traits> &std::basic_ostream<_Elem,_Traits>::operator <<(std::basic_ios<_Elem,_Traits> &(__cdecl *)(std::basic_ios<_Elem,_Traits> &))'
with
[
_Elem=char,
_Traits=std::char_traits<char>
]
c:\program files\microsoft visual studio 8\vc\include\ostream(181): or 'std::basic_ostream<_Elem,_Traits> &std::basic_ostream<_Elem,_Traits>::operator <<(std::ios_base &(__cdecl *)(std::ios_base &))'
with
[
_Elem=char,
_Traits=std::char_traits<char>
]
c:\program files\microsoft visual studio 8\vc\include\ostream(188): or 'std::basic_ostream<_Elem,_Traits> &std::basic_ostream<_Elem,_Traits>::operator <<(std::_Bool)'
with
[
_Elem=char,
_Traits=std::char_traits<char>
]
c:\program files\microsoft visual studio 8\vc\include\ostream(208): or 'std::basic_ostream<_Elem,_Traits> &std::basic_ostream<_Elem,_Traits>::operator <<(short)'
with
[
_Elem=char,
_Traits=std::char_traits<char>
]
c:\program files\microsoft visual studio 8\vc\include\ostream(241): or 'std::basic_ostream<_Elem,_Traits> &std::basic_ostream<_Elem,_Traits>::operator <<(unsigned short)'
with
[
_Elem=char,
_Traits=std::char_traits<char>
]
c:\program files\microsoft visual studio 8\vc\include\ostream(261): or 'std::basic_ostream<_Elem,_Traits> &std::basic_ostream<_Elem,_Traits>::operator <<(int)'
with
[
_Elem=char,
_Traits=std::char_traits<char>
]
c:\program files\microsoft visual studio 8\vc\include\ostream(286): or 'std::basic_ostream<_Elem,_Traits> &std::basic_ostream<_Elem,_Traits>::operator <<(__w64 unsigned int)'
with
[
_Elem=char,
_Traits=std::char_traits<char>
]
c:\program files\microsoft visual studio 8\vc\include\ostream(306): or 'std::basic_ostream<_Elem,_Traits> &std::basic_ostream<_Elem,_Traits>::operator <<(long)'
with
[
_Elem=char,
_Traits=std::char_traits<char>
]
c:\program files\microsoft visual studio 8\vc\include\ostream(326): or 'std::basic_ostream<_Elem,_Traits> &std::basic_ostream<_Elem,_Traits>::operator <<(__w64 unsigned long)'
with
[
_Elem=char,
_Traits=std::char_traits<char>
]
c:\program files\microsoft visual studio 8\vc\include\ostream(347): or 'std::basic_ostream<_Elem,_Traits> &std::basic_ostream<_Elem,_Traits>::operator <<(__int64)'
with
[
_Elem=char,
_Traits=std::char_traits<char>
]
c:\program files\microsoft visual studio 8\vc\include\ostream(367): or 'std::basic_ostream<_Elem,_Traits> &std::basic_ostream<_Elem,_Traits>::operator <<(unsigned __int64)'
with
[
_Elem=char,
_Traits=std::char_traits<char>
]
c:\program files\microsoft visual studio 8\vc\include\ostream(388): or 'std::basic_ostream<_Elem,_Traits> &std::basic_ostream<_Elem,_Traits>::operator <<(float)'
with
[
_Elem=char,
_Traits=std::char_traits<char>
]
c:\program files\microsoft visual studio 8\vc\include\ostream(408): or 'std::basic_ostream<_Elem,_Traits> &std::basic_ostream<_Elem,_Traits>::operator <<(double)'
with
[
_Elem=char,
_Traits=std::char_traits<char>
]
c:\program files\microsoft visual studio 8\vc\include\ostream(428): or 'std::basic_ostream<_Elem,_Traits> &std::basic_ostream<_Elem,_Traits>::operator <<(long double)'
with
[
_Elem=char,
_Traits=std::char_traits<char>
]
c:\program files\microsoft visual studio 8\vc\include\ostream(448): or 'std::basic_ostream<_Elem,_Traits> &std::basic_ostream<_Elem,_Traits>::operator <<(const void *)'
with
[
_Elem=char,
_Traits=std::char_traits<char>
]
c:\program files\microsoft visual studio 8\vc\include\ostream(468): or 'std::basic_ostream<_Elem,_Traits> &std::basic_ostream<_Elem,_Traits>::operator <<(std::basic_streambuf<_Elem,_Traits> *)'
with
[
_Elem=char,
_Traits=std::char_traits<char>
]
while trying to match the argument list '(std::ostream, std::string)'
Build log was saved at "file://c:\Documents and Settings\zj\Desktop\aa\Test\Test\Debug\BuildLog.htm"
Test - 1 error(s), 0 warning(s)
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========


我不明白错在哪里了？？？ 请大家赐教！

[HelloDan]

#include<string>

[Inhibitory]

#include <iostream>

using namespace std;

int main()
{
string str = "hello";

cout < <str < <endl; // 两个"<" 之间没有空格.

return 0;
}

[waizqfor]

帮你改好了 呵呵

#include <iostream> 
#include <string>
using namespace std; 

int main() 
{ 
string str = "hello"; 

cout<<str<<endl; 

return 0; 
} 

[OenAuth.Net]

晕，不用帖这么多错误代码，吓我一跳

[wxgiter]

楼上是正解，把#include <string>加上就OK了。
话说我刚刚也遇到这个错误，一下就搜到你这个帖子了～～呵呵