c++ - 使用 boost 字符串库在 visual studio 中获取字符串编译错误

Question

我正在尝试制作一个从 ini 文件读取的程序，但在 Visual Studio 中，我一直在错误的位置收到有关字符串标识符和分号的编译错误。我不是很擅长 C++，所以它很可能是非常简单的东西，但无论如何这里都是代码和错误列表。

INI.h

#ifndef INI_H
#define INI_H

#include <boost/property_tree/ptree.hpp>
#include <boost/property_tree/ini_parser.hpp>
#include <boost/algorithm/string.hpp>
#include <iostream>

string INIreader(const string&, const string&);

#endif

INI_readnwrite.cpp

#include "INI.h"

using boost::property_tree::ptree;

string INIreader(const string& section, const string& name)
{
    ptree pt;
    read_ini("GameSettings.ini", pt);
    string value = pt.get<string>("section.name");
    return value;
}

mainCode.cpp

#include "INI.h"

using namespace std;
int main()
{
    string sec = "gameSettings";
    string val = "resXY";
    cout << INIreader(sec, val);
}

这是错误列表

error// file//  line//
error C2872: 'string' : ambiguous symbol    maincode.cpp    18
error C2146: syntax error : missing ';' before identifier 'sec' maincode.cpp    18
error C2065: 'sec' : undeclared identifier  maincode.cpp    18
error C2872: 'string' : ambiguous symbol    maincode.cpp    19
error C2146: syntax error : missing ';' before identifier 'val' maincode.cpp    19
error C2065: 'val' : undeclared identifier  maincode.cpp    19
error C2065: 'val' : undeclared identifier  maincode.cpp    20
error C2065: 'sec' : undeclared identifier  maincode.cpp    20
error C4430: missing type specifier - int assumed. Note: C++ does not support default-int   ini_readnwrite.cpp  6
error C2872: 'string' : ambiguous symbol    ini_readnwrite.cpp  6
error C2146: syntax error : missing ';' before identifier 'INIreader'   ini_readnwrite.cpp  6
error C2143: syntax error : missing ',' before '&'  ini_readnwrite.cpp  6
error C2086: 'int string' : redefinition    ini_readnwrite.cpp  6
error C4430: missing type specifier - int assumed. Note: C++ does not support default-int   ini_readnwrite.cpp  7
error C2974: 'boost::property_tree::basic_ptree<std::string,std::string,std::less<Key>>::get' : invalid template argument for 'Type', type expected ini_readnwrite.cpp  10
error C2974: 'boost::property_tree::basic_ptree<std::string,std::string,std::less<Key>>::get' : invalid template argument for 'Ch', type expected   ini_readnwrite.cpp  10
error C2146: syntax error : missing ';' before identifier 'value'   ini_readnwrite.cpp  10
error C2065: 'value' : undeclared identifier    ini_readnwrite.cpp  10
error C2065: 'value' : undeclared identifier    ini_readnwrite.cpp  11
IntelliSense: identifier "string" is undefined  INI.h   9
IntelliSense: identifier "string" is undefined  INI.h   9
IntelliSense: identifier "string" is undefined  INI.h   9
error C4430: missing type specifier - int assumed. Note: C++ does not support default-int   ini.h   9
error C4430: missing type specifier - int assumed. Note: C++ does not support default-int   ini.h   9
error C2146: syntax error : missing ';' before identifier 'INIreader'   ini.h   9
error C2146: syntax error : missing ';' before identifier 'INIreader'   ini.h   9
error C2143: syntax error : missing ',' before '&'  ini.h   9
error C2143: syntax error : missing ',' before '&'  ini.h   9

谢谢。

Answer 1

当您尝试在头文件中使用 std::string 时，您需要使用完全限定名称:

std::string INIreader(const std::string&, const std::string&);

然后在 INI_readnwrite.cpp 中做同样的事情，或者像在其他 .cpp 文件中那样添加一个“using”指令:

using boost::property_tree::ptree;
using namespace std;