Question

如何检查C中字符串中的给定子字符串是否？下面的代码比较它们是否相等，但是如果在另一个内部有一个。

#include <stdio.h>
#include <string.h>
int main( )
{
   char str1[ ] = "test" ;
   char str2[ ] = "subtest" ;
   int i, j, k ;
   i = strcmp ( str1, "test" ) ;
   j = strcmp ( str1, str2 ) ;
   k = strcmp ( str1, "t" ) ;
   printf ( "\n%d %d %d", i, j, k ) ;
   return 0;
}

Answer 1

当然，正如@paddy指出的那样

inline bool issubstr(const char *string, const char *substring )
{
    return( strstr(string, substring) ) ?  true: false ;
}

ststr返回指向子字符串开头的指针，如果是，则返回NULL 找不到子字符串。

更多关于strstr和朋友man page strstr

Answer 2

您可以使用strstr() paddy

提到的功能

 strstr() function returns the first occurance of the substring in a string.  If you are to find all occurances of a substring in a string than you have to use "String matching " algorithms such as,    
1)Naive String Matching
2)Rabin Karp   
3)Knuth Morris Pratt

Answer 3

你可以使用strstr

char str1[ ] = "subtest";
char str2[ ] = "test";
int index = -1;
char * found = strstr( str1, str2);

if (found != NULL)
{
  index = found - str1;
}

Answer 4

在strstr

中使用<string.h>

char* str = "This is a test";
char* sub = "is";
char* pos = strstr(str, sub);
if (pos != NULL)
    printf("Found the string '%s' in '%s'\n", sub, str);

输出：

Found the string 'is' in 'This is a test'

使用C

4 个答案: