函数原型：

int _stricmp( const char
*string1, const char *string2
);        //#include <string.h>

int _wcsicmp( const wchar_t
*string1, const wchar_t
*string2 );    //#include <string.h> or  <wchar.h>

int _mbsicmp( const unsigned char
*string1, const unsigned char_t
*string2 );    //#include <mbstring.h>

返回值：

： string1 identical to string2         <0：string1 less than  string2             >0：string1 greater than string2

举例：
char *str1 = "abc";
char *str2 = "AbC";
int  nResult = _stricmp(str1, str2);         //nResult = 0

wchar_t szStr1[] = "asdfg";
wchar_t szStr2[] = "AsDfG";
int nResult = _wcsicmp(szStr1, szStr2);      //nResult = 0

至于_mbsicmp是比较无符号字符串的，可根据情况自行使用