C + + Implementation software version number comparison

Software version number of the check and comparison is a feature that we often use, I wrote a function, it is very convenient to use.

function function: Perform version comparison in string form//return value: Compare successful return true, compare failure return false//Compare result save to Nresult//LpszVer1 above LpszVer2 nresult value is 1//LP SzVer1 lower than lpszVer2 when the value of Nresult is -1//lpszVer1 equals lpszVer2 when Nresult value is 0//usage Description: The safe usage should be to judge the function return value first, Return to True when checking for comparison results in nresult bool Compareversion (__in lpctstr lpszVer1, __in lpctstr lpszVer2, __out Short & Nresult) {//Parameter security Sex Check if (lpszVer1 = = NULL | | lpszver1[0] = _t (' lpszVer2 ')) return false;if (= = NULL | | lpszver2[0] = = _t (') ') return FAL se;//parameter validity check for (size_t i = 0; i < _tcslen (lpszVer1); i++) {//If the current character in the specified version number is outside the range of 0 to 9 and is not a split point, it is considered invalid if ((Lpszver1[i] &l T _t (' 0 ') | | Lpszver1[i] > _t (' 9 ') && lpszver1[i]! = _t ('. ')) return FALSE;}  for (size_t i = 0; i < _tcslen (lpszVer2); i++) {//If the current character in the specified version number is outside the range 0 to 9 and is not a split point, it is considered invalid if ((Lpszver2[i] < _t (' 0 ') | | Lpszver2[i] > _t (' 9 ') && lpszver2[i]! = _t ('. ')) return FALSE;} The _tcstok_s function modifies the input, so the version string is copied a copy//according to the usual notation of the version number, it is not necessary to request space from the heap based on the size of the source version string, directly defined to meet the overwhelming majority of requirements, but also to raise the high efficiency of the const short Nmax_ver_len = 64; TCHAR SzveR1[nmax_ver_len] = {0}, Szver2[nmax_ver_len] = {0}; StringCchCopy (SzVer1, nmax_ver_len-1, lpszVer1); StringCchCopy (SzVer2, nmax_ver_len-1, lpszVer2); const TCHAR szseps[] = _t ("."); LPTSTR lpszToken1 = null, lpszToken2 = NULL; LPTSTR lpszNextToken1 = NULL, lpszNextToken2 = Null;lpsztoken1 = _tcstok_s (SzVer1, Szseps, &AMP;LPSZNEXTTOKEN1); LpszToken2 = _tcstok_s (SzVer2, Szseps, &lpsznexttoken2);//Progressive split while ((LpszToken1! = NULL) | | (LpszToken2! = NULL))  {int nNum1 = 0, nNum2 = 0;//checks the split result if (lpszToken1! = NULL) {nNum1 = _tstoi (lpszToken1); lpszToken1 = _tcstok_s (NULL, Szseps, &AMP;LPSZNEXTTOKEN1);} if (lpszToken2! = NULL) {nNum2 = _tstoi (lpszToken2); lpszToken2 = _tcstok_s (NULL, Szseps, &lpsznexttoken2);} Perform comparison if (NNum1 > nNum2) {nresult = 1;break;} else if (NNum1 < nNum2) {nresult = -1;break;} Else{nresult = 0;}} return TRUE;}

C + + Implementation software version number comparison