常見的C字符串處理函數(shù)的源代碼-

1、以下是一些常見的C字符串處理函數(shù)的源代碼,當(dāng)然也是從網(wǎng)上找來的,學(xué)習(xí)它一個(gè)好處是加深理解C,另一個(gè)好外是應(yīng)聘面試中的筆試常常會用到它們,呵呵。當(dāng)然,還有一些沒有列出來,或者有更好的實(shí)現(xiàn)方法,你可以貢獻(xiàn)一下哦,share your code! :/stirng.c= =char *strcpy(char *strDes, const char *strSrcassert(strDes != NULL && (strSrc != NULL;/如果條件為假,就打印具體出錯(cuò)的問題char *address = strDes;while (*strDes + = *strSrc + !=

2、 '0' NULL;return address;char *strchr_(char *str, int cassert(str != NULL;while (*str != (char c && (*str != '0'str +;if (*str != '0'return str;return NULL;char *strchr(const char *str, int cassert(str != NULL;for (; *str != (char c; + strif (*str = '0'return

3、NULL;return (char * str;int strcmp(const char *s, const char *tassert(s != NULL && t != NULL;while (*s && *t && *s = *t+ s;+ t;return (*s - *t;char *strcat(char *strDes, const char *strSrcassert(strDes != NULL && (strSrc != NULL;char *address = strDes;while (*strDes !

4、= '0'+ strDes;while (*strDes + = *strSrc + != '0' NULL;return address;int strlen(const char *strassert(str != NULL;int len = 0;while (*str + != '0'+ len;return len;char *strdup(const char *strSrcassert(strSrc != NULL;int len = 0;while (*strSrc + != '0'+ len;char *strD

5、es = (char * malloc (len + 1;while (*strDes + = *strSrc + != '0' NULL;return strDes;char *strstr(const char *strSrc, const char *strassert(strSrc != NULL && str != NULL;const char *s = strSrc;const char *t = str;for (; *t != '0' + strSrcfor (s = strSrc, t = str; *t != '0&

6、#39; && *s = *t; +s, +tNULL;if (*t = '0'return (char * strSrc;return NULL;char *strncpy(char *strDes, const char *strSrc, int countassert(strDes != NULL && strSrc != NULL;char *address = strDes;while (count - && *strSrc != '0'*strDes + = *strSrc +;return addre

7、ss;char *strncat(char *strDes, const char *strSrc, int countassert(strDes != NULL && (strSrc != NULL;char *address = strDes;while (*strDes != '0'+ strDes;while (count - && *strSrc != '0' *strDes + = *strSrc +;*strDes = '0'return address;int strncmp(const char

8、*s, const char *t, int countassert(s != NULL && (t != NULL;while (*s && *t && *s = *t && count -+ s;+ t;return (*s - *t;char *strpbrk(const char *strSrc, const char *strassert(strSrc != NULL && (str != NULL;const char *s;while (*strSrc != '0's = str;wh

9、ile (*s != '0'if (*strSrc = *sreturn (char * strSrc;+ s;+ strSrc;return NULL;int strcspn(const char *strSrc, const char *strassert(strSrc != NULL && (str != NULL;const char *s;const char *t = strSrc;while (*t != '0's = str;while (*s != '0'if (*t = *sreturn t - strSrc;

10、+ s;+ t;return 0;int strspn(const char *strSrc, const char *strassert(strSrc != NULL && (str != NULL;const char *s;const char *t = strSrc;while (*t != '0's = str;while (*s != '0'if (*t = *sbreak;+ s;if (*s = '0'return t - strSrc;+ t;return 0;char *strrchr(const char *

11、str, int c assert(str != NULL;const char *s = str;while (*s != '0'+ s;for (- s; *s != (char c; - sif (s = strreturn NULL;return (char * s;char* strrev(char *strassert(str != NULL;char *s = str, *t = str, c;while (*t != '0'+ t;for (- t; s < t; + s, - tc = *s;*s = *t;*t = c;return s

12、tr;char *strnset(char *str, int c, int count assert(str != NULL;char *s = str;for (; *s != '0' && s - str < count; + s *s = (char c;return str;char *strset(char *str, int cassert(str != NULL;char *s = str;for (; *s != '0' + s*s = (char c;return str;char *strtok(char *strTo

13、ken, const char *strassert(strToken != NULL && str != NULL;char *s = strToken;const char *t = str;while (*s != '0't = str;while (*t != '0'if (*s = *t*(strToken + (s - strToken = '0'return strToken;+ t;+ s;return NULL;char *strupr(char *strassert(str != NULL;char *s =

14、str;while (*s != '0'if (*s >= 'a' && *s <= 'z'*s -= 0x20;s +;return str;char *strlwr(char *strassert(str != NULL;char *s = str;while (*s != '0'if (*s >= 'A' && *s <= 'Z'*s += 0x20;s +;return str;void *memcpy(void *dest, cons

15、t void *src, int countassert(dest != NULL && (src != NULL;void *address = dest;while (count -*(char * dest = *(char * src;dest = (char * dest + 1;src = (char * src + 1;return address;void *memccpy(void *dest, const void *src, int c, unsigned int countassert(dest != NULL && (src != NU

16、LL;while (count -*(char * dest = *(char * src;if (* (char * src = (char creturn (char *dest + 1;dest = (char * dest + 1; src = (char * src + 1; return NULL; void *memchr(const void *buf, int c, int count assert(buf != NULL; while (count - if (*(char * buf = c return (void * buf; buf = (char * buf +

17、1; return NULL; int memcmp(const void *s, const void *t, int count assert(s != NULL && (t != NULL; while (*(char * s && *(char * t && *(char * s = *(char * t && count - s = (char * s + 1; t = (char * t + 1; return (*(char * s - *(char * t; void *memmove(void *dest, const void *src, int count assert(dest != NULL && src != NULL; void *ad