Question

我正在编写一些代码，它应该做的是将路径返回到没有文件名本身的文件。这是

#include <iostream>
#include <string>
#include <Windows.h>
using namespace std;

int main() {
    char binaryPath[MAX_PATH]; //I think my problems stem from the fact that 
                               //isnt truly a string

    GetModuleFileName(NULL, binaryPath, MAX_PATH); //Get filename
    string i = (string) binaryPath;
    string fileDir = "";
    int tempSlashes = 0;
    for (int x = 0; x < strlen(binaryPath); x++) {
        if (i[x] == '\\') { //In eclipse CDT this gives warning 1 (below)
            tempSlashes++; 
        }
    }
    for (int y = 0; y < tempSlashes; y++) {
        fileDir.append(binaryPath[y]); //Line gives warning 2
    }
    cout << fileDir;
    return 0;
}

无论如何，小警告注释

Error 1:
Multiple markers at this line
- comparison with string literal results in unspecified behaviour [-
 Waddress]
- ISO C++ forbids comparison between pointer and integer [-
 fpermissive]

Error 2:
Multiple markers at this line
- Invalid arguments ' Candidates are: std::basic_string<char,std::char_traits<char>,std::allocator<char>> & append(const 
 std::basic_string<char,std::char_traits<char>,std::allocator<char>> &) std::basic_string<char,std::char_traits<char>,std::allocator<char>> & append(const 
 std::basic_string<char,std::char_traits<char>,std::allocator<char>> &, unsigned int, unsigned int) std::basic_string<char,std::char_traits<char>,std::allocator<char>> & append(const 
 char *, unsigned int) std::basic_string<char,std::char_traits<char>,std::allocator<char>> & append(const char *) std::basic_string<char,std::char_traits<char>,std::allocator<char>> & 
 append(unsigned int, char) std::basic_string<char,std::char_traits<char>,std::allocator<char>> & append(#10000, #10000) '
- invalid conversion from 'char' to 'const char*' [-fpermissive]

程序本身拒绝编译，并运行早期的.exe

我不确定我在这里做错了什么，帮助（以及解释）会非常好。

谢谢！

Answer 1

我建议向后迭代并寻找＆＃39; \＆＃39;。类似的东西：

int len = strlen(binaryPath);
char outPath[MAX_PATH];
strcpy(outPath, binaryPath);
for (int x = len - 1; x >= 0; --x) {
    outPath[x] = 0;
    if (binaryPath[x] == '\\') {
        break;
    }
}

Answer 2

首先，在现代的Win32 C ++代码中，您可能希望使用 Unicode 而不是ANSI / MBCS（因此，wchar_t代替char和std::wstring而不是std::string）。

对于您的特定问题，您可能希望使用现有的Win32 API：PathRemoveFileSpec()。

以下是可编辑的示例代码：

#define UNICODE
#define _UNICODE
#include <iostream>
#include <string>
#include <Windows.h>
#include <Shlwapi.h>
using namespace std;

#pragma comment(lib, "Shlwapi.lib")

int main()
{
    wchar_t binaryPath[MAX_PATH];
    GetModuleFileName(nullptr, binaryPath, MAX_PATH);
    PathRemoveFileSpec(binaryPath);

    // You can assign to a std::wstring as well...
    wstring fileDir = binaryPath;

    wcout << fileDir << endl;
}

以下是一个示例测试：

C:\Temp\CppTests>cl /EHsc /W4 /nologo /MTd test.cpp
test.cpp

C:\Temp\CppTests>test.exe
C:\Temp\CppTests

作为替代方案，一旦在原始C缓冲区中读取了文件名的完整路径：

wchar_t binaryPathBuffer[MAX_PATH];
GetModuleFileName(nullptr, binaryPathBuffer, MAX_PATH);

您可以将其复制到std::wstring，然后使用其 rfind() 方法查找上一个'\'的位置，然后提取正确的使用substr

的 std::wstring 方法的子字符串

wstring binaryPath = binaryPathBuffer;
size_t last = binaryPath.rfind(L'\\');
wstring fileDir = binaryPath.substr(0, last);

比较和附加字符串的问题c ++

2 个答案: