如何将#include <iostream> 添加到项目中?
How to add #include <iostream> to project?
我刚开始学习 C++,我试图用 Visual Studio 2017 创建一个简单的代码。
#include "stdafx.h"
#include <iostream>
using namespace std;
int main()
{
int x;
std::cout >> "Enter Age";
std::cin >> x;
if (x >= 18) {
std::cout << "You are an adult." << endl;
}
else {
std::cout << "You are a child." << endl;
}
return 0;
}
但我认为我遇到了很多错误,例如 iostream 不存在 因为我没有在头文件中看到它或 iostream.h
我尝试创建一个新的头文件并简单地键入 #include <iostream>
但这似乎不起作用。这是我的错误。
1>c:\users\munta\onedrive\documents\visual studio
2017\projects\consoleapplication3\consoleapplication3\source.cpp(8): error
C2784: 'std::basic_istream<char,_Traits> &std::operator >>
(std::basic_istream<char,_Traits> &,signed char &)': could not deduce
template argument for 'std::basic_istream<char,_Traits> &' from
'std::ostream'
1>c:\program files (x86)\microsoft visual
studio17\community\vc\tools\msvc.10.25017\include\istream(1068):
note: see declaration of 'std::operator >>'
1>c:\users\munta\onedrive\documents\visual studio
2017\projects\consoleapplication3\consoleapplication3\source.cpp(8): error
C2784: 'std::basic_istream<char,_Traits> &std::operator >>
(std::basic_istream<char,_Traits> &,signed char *)': could not deduce
template argument for 'std::basic_istream<char,_Traits> &' from
'std::ostream'
1>c:\program files (x86)\microsoft visual
studio17\community\vc\tools\msvc.10.25017\include\istream(1061):
note: see declaration of 'std::operator >>'
1>c:\users\munta\onedrive\documents\visual studio
2017\projects\consoleapplication3\consoleapplication3\source.cpp(8): error
C2784: 'std::basic_istream<_Elem,_Traits> &std::operator >>
(std::basic_istream<_Elem,_Traits> &,_Elem &)': could not deduce template
argument for 'std::basic_istream<_Elem,_Traits> &' from 'std::ostream'
1>c:\program files (x86)\microsoft visual
studio17\community\vc\tools\msvc.10.25017\include\istream(1036):
note: see declaration of 'std::operator >>'
1>c:\users\munta\onedrive\documents\visual studio
2017\projects\consoleapplication3\consoleapplication3\source.cpp(8): error
C2784: 'std::basic_istream<_Elem,_Traits> &std::operator >>
(std::basic_istream<_Elem,_Traits> &,_Elem *)': could not deduce template
argument for 'std::basic_istream<_Elem,_Traits> &' from 'std::ostream'
1>c:\program files (x86)\microsoft visual
studio17\community\vc\tools\msvc.10.25017\include\istream(995): note:
see declaration of 'std::operator >>'
1>c:\users\munta\onedrive\documents\visual studio
2017\projects\consoleapplication3\consoleapplication3\source.cpp(8): error
C2676: binary '>>': 'std::ostream' does not define this operator or a
conversion to a type acceptable to the predefined operator
1>Done building project "ConsoleApplication3.vcxproj" -- FAILED.
感谢您的帮助。
检查这个:std::cout >> "Enter Age";
。我想应该是 std::cout << "Enter Age";
。
顺便说一句,与问题无关,因为你正在写 std::cout
和 std::cin
那么如果你保持与 std::endl
而不是 [=15= 的一致性会更好].
问题在第 8 行。应该是:
std::cout << "Enter Age";
我刚开始学习 C++,我试图用 Visual Studio 2017 创建一个简单的代码。
#include "stdafx.h"
#include <iostream>
using namespace std;
int main()
{
int x;
std::cout >> "Enter Age";
std::cin >> x;
if (x >= 18) {
std::cout << "You are an adult." << endl;
}
else {
std::cout << "You are a child." << endl;
}
return 0;
}
但我认为我遇到了很多错误,例如 iostream 不存在 因为我没有在头文件中看到它或 iostream.h
我尝试创建一个新的头文件并简单地键入 #include <iostream>
但这似乎不起作用。这是我的错误。
1>c:\users\munta\onedrive\documents\visual studio
2017\projects\consoleapplication3\consoleapplication3\source.cpp(8): error
C2784: 'std::basic_istream<char,_Traits> &std::operator >>
(std::basic_istream<char,_Traits> &,signed char &)': could not deduce
template argument for 'std::basic_istream<char,_Traits> &' from
'std::ostream'
1>c:\program files (x86)\microsoft visual
studio17\community\vc\tools\msvc.10.25017\include\istream(1068):
note: see declaration of 'std::operator >>'
1>c:\users\munta\onedrive\documents\visual studio
2017\projects\consoleapplication3\consoleapplication3\source.cpp(8): error
C2784: 'std::basic_istream<char,_Traits> &std::operator >>
(std::basic_istream<char,_Traits> &,signed char *)': could not deduce
template argument for 'std::basic_istream<char,_Traits> &' from
'std::ostream'
1>c:\program files (x86)\microsoft visual
studio17\community\vc\tools\msvc.10.25017\include\istream(1061):
note: see declaration of 'std::operator >>'
1>c:\users\munta\onedrive\documents\visual studio
2017\projects\consoleapplication3\consoleapplication3\source.cpp(8): error
C2784: 'std::basic_istream<_Elem,_Traits> &std::operator >>
(std::basic_istream<_Elem,_Traits> &,_Elem &)': could not deduce template
argument for 'std::basic_istream<_Elem,_Traits> &' from 'std::ostream'
1>c:\program files (x86)\microsoft visual
studio17\community\vc\tools\msvc.10.25017\include\istream(1036):
note: see declaration of 'std::operator >>'
1>c:\users\munta\onedrive\documents\visual studio
2017\projects\consoleapplication3\consoleapplication3\source.cpp(8): error
C2784: 'std::basic_istream<_Elem,_Traits> &std::operator >>
(std::basic_istream<_Elem,_Traits> &,_Elem *)': could not deduce template
argument for 'std::basic_istream<_Elem,_Traits> &' from 'std::ostream'
1>c:\program files (x86)\microsoft visual
studio17\community\vc\tools\msvc.10.25017\include\istream(995): note:
see declaration of 'std::operator >>'
1>c:\users\munta\onedrive\documents\visual studio
2017\projects\consoleapplication3\consoleapplication3\source.cpp(8): error
C2676: binary '>>': 'std::ostream' does not define this operator or a
conversion to a type acceptable to the predefined operator
1>Done building project "ConsoleApplication3.vcxproj" -- FAILED.
感谢您的帮助。
检查这个:std::cout >> "Enter Age";
。我想应该是 std::cout << "Enter Age";
。
顺便说一句,与问题无关,因为你正在写 std::cout
和 std::cin
那么如果你保持与 std::endl
而不是 [=15= 的一致性会更好].
问题在第 8 行。应该是:
std::cout << "Enter Age";