About character arrays in C, character pointers, and 22 conversions and sorting of string types in C + +

//practise.cpp: Defines the entry point of the console application. //#include"stdafx.h"#include<string.h>#include<string>#include<algorithm>#include<iostream>using namespacestd;intMain () {/*string to character array, using strncpy_s (), than strncpy () security*/    stringstr ="ABC xyz"; Charstrarray[ One] = {0};    strncpy_s (Strarray, Str.c_str (), str.length ()); printf ("Strarray:%s\n", Strarray); cout<< Strarray <<Endl; /*string to character pointer, call C_STR () directly*/    Const Char* Strpointer =""; Strpointer=Str.c_str (); printf ("Strpointer:%s\n", Strpointer); cout<< Strpointer <<Endl; /*the character pointer is converted into a string, directly assigned to the value*/    Char* StrPointer1 ="bat Hzx"; stringSTR1 =StrPointer1; printf ("str1:%s\n", Str1.c_str ()); /*the character array is converted to a string, directly assigned to a value*/    CharStrarray1[] ="hzx Bat"; stringSTR2 =StrArray1; printf ("str2:%s\n", Str2.c_str ()); /*the character pointer is converted into a character array, strncpy_s ()*/    Char* StrPointer2 ="Cheng du"; //int strLen = StrLen (StrPointer2); //char Strarray2[strlen] = {0};//error C2057: The constant expression should be entered    Charstrarray2[ One] = {0};    strncpy_s (StrArray2, StrPointer2, strlen (StrPointer2)); printf ("strArray2:%s\n", StrArray2); /*character array into character pointer, direct assignment*/    Charstrarray3[ -] ="Beijing China"; Char*StrPointer3; StrPointer3=StrArray3; printf ("StrPointer3:%s\n", StrPointer3); /*how the character array compares size, using the strcmp () function*/    Charstrarray4[8] ="ABC"; Charstrarray5[8] ="ABX"; Charstrarray6[8] ="ABC"; printf ("StrArray4:%d strArray5:%d strArray6:%d\n", StrArray4, StrArray5, StrArray6); printf ("Is big:%d\n", strcmp (StrArray4, strArray5)); printf ("Is big:%d\n", strcmp (StrArray4, StrArray6)); printf ("Is big:%d\n", strcmp (StrArray5, StrArray6)); /*How the character pointer compares size, using the strcmp () function*/    Char* StrArray7 ="ABC"; Char* StrArray8 ="Aby"; Char* StrArray9 ="ABC"; printf ("StrArray7:%d StrArray8:%d strArray9:%d\n", StrArray7, StrArray8, StrArray9); printf ("Is big:%d\n", strcmp (StrArray7, StrArray8)); printf ("Is big:%d\n", strcmp (StrArray7, StrArray9)); printf ("Is big:%d\n", strcmp (StrArray8, StrArray9)); /*how character pointers and character arrays compare size, using the strcmp () function*/    Char* StrArray10 ="ABC"; Charstrarray11[5] ="Abz"; Char* StrArray12 ="ABC"; printf ("StrArray10:%d StrArray11:%d strArray12:%d\n", StrArray10, StrArray11, STRARRAY12); printf ("Is big:%d\n", strcmp (StrArray10, StrArray11)); printf ("Is big:%d\n", strcmp (StrArray10, strArray12)); printf ("Is big:%d\n", strcmp (StrArray11, strArray12)); /*How the string compares size, using strcmp () +c_str () combination or direct compare ()*/    stringStr13 ="ABC"; stringStr14 ="ABX"; stringStr15 ="ABC"; printf ("Str13:%d str14:%d str15:%d\n", Str13, Str14, STR15); printf ("Is big:%d\n", strcmp (Str13.c_str (), Str14.c_str ())); printf ("Is big:%d\n", strcmp (Str13.c_str (), Str15.c_str ())); printf ("Is big:%d\n", strcmp (Str14.c_str (), Str15.c_str ())); cout<< Str13.compare (str14) <<Endl; cout<< Str13.compare (STR15) <<Endl; cout<< Str14.compare (STR15) <<Endl; return 0;}

About character arrays in C, character pointers, and 22 conversions and sorting of string types in C + +