c++ - '昏暗' : identifier not found

Question

我收到此错误消息:

error C3861: 'dim': identifier not found

这是我的包括:

#include "stdafx.h"
#include "HSMBTPrintX.h"
#include "HSMBTPrintXCtrl.h"
#include "HSMBTPrintXPropPage.h"


#ifdef _DEBUG
#define new DEBUG_NEW
#endif

这是我的功能:

#define MSS_PORTS_BASE _T("Software\\Microsoft\\Bluetooth\\Serial\\Ports")
bool FindBluetoothPort(TCHAR name[16]) {
    HKEY hKey, hRoot;
    TCHAR szPort[20] = _T(""), szPortString[20];
    DWORD len, dwIndex=0;
    bool bFound=false;
    INT i = 0, rc;
    DWORD dwNSize;
    DWORD dwCSize;
    TCHAR szClass[256];
    TCHAR szName[MAX_PATH];
    FILETIME ft;
    hRoot = HKEY_LOCAL_MACHINE;
    if (RegOpenKeyEx (hRoot, MSS_PORTS_BASE, 0, 0, &hKey) != ERROR_SUCCESS) {
        rc = GetLastError();
        return 0;
    }
    dwNSize = dim(szName);    <---- ~~ !! HERE IS THE LINE THAT ERRORS
    dwCSize = dim(szClass);     <---- HERE IS THE LINE THAT ERRORS  !! 
    rc = RegEnumKeyEx (hKey, i, szName, &dwNSize, NULL, szClass, &dwCSize, &ft);
    while (rc == ERROR_SUCCESS)
    {
        // how many children
        TCHAR szCurrentKey[MAX_PATH];
        wcscpy(szCurrentKey, MSS_PORTS_BASE);
        wcscat(szCurrentKey, TEXT("\\"));
        wcscat(szCurrentKey, szName);
        wcscat(szCurrentKey, TEXT("\\"));
        len = sizeof(szPort);
        if(RegGetValue(hRoot, szCurrentKey, _T("Port"), NULL, (LPBYTE)szPort, &len)) {
            wsprintf(szPortString, _T("%s:"), szPort);
            bFound = true;
            break;
        }
        dwNSize = dim(szName);
        rc = RegEnumKeyEx(hKey, ++i, szName, &dwNSize, NULL, NULL, 0, &ft);
    }

    if(bFound)
        _tcscpy(name, szPortString);

    return bFound;
}

如您所见，使用它的两行是:

dwNSize = dim(szName);

dwCSize = dim(szClass);

为什么会出错？

Answer 1

看起来你想要sizeof:

dwNSize = sizeof(szName);
dwCSize = sizeof(szClass);

sizeof 返回对象/变量的字节数。但是，我刚刚查看了 API RegEnumKeyEx 的文档，它需要字符数。所以我认为它实际上应该除以 TCHAR 的大小(这将是 1 或 2，具体取决于您是否为 Unicode 构建)。

dwNSize = sizeof(szName) / sizeof(TCHAR);
dwCSize = sizeof(szClass) / sizeof(TCHAR);