windows c++ 比较字符串不区分大小写_c++ strstr 不区分大小写-优快云博客

本文介绍了StrStrI函数的功能及用法，该函数用于在字符串中查找子串首次出现的位置，且比较时不区分大小写。文章对比了StrStrI与其他字符串搜索函数的不同，并通过示例代码展示了如何使用此函数。

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//z 2014-04-18 17:41:49 BG57IV3@XCL T745044962 .K.F253293061 [T244,L3296,R157,V4779]
使用函数 StrStrI 比较字符串，不区分大小写。
StrStrI function
Finds the first occurrence of a substring within a string. The comparison is not case-sensitive.
Return value

包含头文件 Shlwapi.h
库 Shlwapi.lib
注意：与 wcstr 不同，在传入一个空字符串时，会返回 NULL 。

Type: PTSTR
Returns the address of the first occurrence of the matching substring if successful, or NULL otherwise.


Header Shlwapi.h
Library Shlwapi.lib


nlike strstr() and wcsstr() passing an emtpy string results in NULL being returned.


pszFound = StrStrI(L"abcdefg", L""); // returns NULL
pszFoundStrStr = wcsstr(L"abcdefg", L""); // returns L"abcdefg"


char *strstr(
   const char *str,
   const char *strSearch 
); // C only
char *strstr(
   char *str,
   const char *strSearch 
); // C++ only
const char *strstr(
   const char *str,
   const char *strSearch 
); // C++ only
wchar_t *wcsstr(
   const wchar_t *str,
   const wchar_t *strSearch 
); // C only
wchar_t *wcsstr(
   wchar_t *str,
   const wchar_t *strSearch 
); // C++ only
const wchar_t *wcsstr(
   const wchar_t *str,
   const wchar_t *strSearch 
); // C++ only
unsigned char *_mbsstr(
   const unsigned char *str,
   const unsigned char *strSearch 
); // C only
unsigned char *_mbsstr(
   unsigned char *str,
   const unsigned char *strSearch 
); // C++ only
const unsigned char *_mbsstr(
   const unsigned char *str,
   const unsigned char *strSearch 
); // C++ only
unsigned char *_mbsstr_l(
   const unsigned char *str,
   const unsigned char *strSearch,
   _locale_t locale
); // C only
unsigned char *_mbsstr_l(
   unsigned char *str,
   const unsigned char *strSearch,
   _locale_t locale
); // C++ only
const unsigned char *_mbsstr_l(
   const unsigned char *str,
   const unsigned char *strSearch,
   _locale_t locale
); // C++ only

//z 2014-04-18 17:41:49 BG57IV3@XCL T745044962 .K.F253293061 [T244,L3296,R157,V4779]

Generic-Text Routine Mappings
TCHAR.H
 routine _UNICODE
 & _MBCS not defined _MBCS
 defined _UNICODE
 defined
_tcsstr strstr _mbsstr wcsstr
n/a n/a _mbsstr_l n/a

// crt_strstr.c

#include <string.h>
#include <stdio.h>

char str[] =    "lazy";
char string[] = "The quick brown dog jumps over the lazy fox";
char fmt1[] =   "         1         2         3         4         5";
char fmt2[] =   "12345678901234567890123456789012345678901234567890";

int main( void )
{
   char *pdest;
   int  result;
   printf( "String to be searched:\n   %s\n", string );
   printf( "   %s\n   %s\n\n", fmt1, fmt2 );
   pdest = strstr( string, str );
   result = (int)(pdest - string + 1);
   if ( pdest != NULL )
      printf( "%s found at position %d\n", str, result );
   else
      printf( "%s not found\n", str );
}
/* strstr example */
#include <stdio.h>
#include <string.h>

int main ()
{
  char str[] ="This is a simple string";
  char * pch;
  pch = strstr (str,"simple");
  strncpy (pch,"sample",6);
  puts (str);
  return 0;
}


String to be searched:
   The quick brown dog jumps over the lazy fox
            1         2         3         4         5
   12345678901234567890123456789012345678901234567890

lazy found at position 36