将char转换为std :: string不起作用

Question

我正在尝试列出我的Pc的逻辑驱动器并将结果添加到矢量但我得到这个奇怪的result = ;;;.

我在这里失踪了什么？

std::vector<std::string> directory::getLogicalDrives() {
    DWORD mydrives = 100;
    char lpBuffer[100];
    DWORD drives = GetLogicalDriveStrings(mydrives, lpBuffer);

    std::vector<std::string> driveList;
    for (int i = 0; i < 100; i++) {
        std::string drive(3, '%c' + lpBuffer[0]); // Missing something?
        driveList.push_back(drive);
    }
    return driveList;
}

Answer 1

如文档 中所述,GetLogicalDriveStrings()为您提供以NULL结尾的字符串列表,列表以NULL字符终止.所以只需迭代该列表,例如:

std::vector<std::string> directory::getLogicalDrives() {
    std::vector<std::string> driveList;
    char szBuffer[105];
    DWORD size = GetLogicalDriveStrings(104, szBuffer);
    if ((size > 0) && (size <= 104)) {
        const char *pstr = szBuffer;
        while( *pstr ) {
            std::string drive( pstr );
            driveList.push_back(drive);
            pstr += (drive.length() + 1);
        }
    }
    return driveList;
}