说起字符串函数,我想大家都不陌生。字符串函数对二进制数据、字符串和表达式执行不同的运算。下面总结了C语言中的字符串函数。
1、函数名: stpcpy
功 能: 拷贝一个字符串到另一个
用 法:
- char *stpcpy(char *destin, char *source);
程序例:
- #include <stdio.h>
- #include <string.h>
- int main(void)
- {
- char string[10];
- char *str1 = "abcdefghi";
- stpcpy(string, str1);
- printf("%s\n", string);
- return 0;
- }
2、函数名: strcat
功 能: 字符串拼接函数
用 法:
- char *strcat(char *destin, char *source);
程序例:
- #include <string.h>
- #include <stdio.h>
- int main(void)
- {
- char destination[25];
- char *blank = " ", *c = "C++", *Borland = "Borland";
- strcpy(destination, Borland);
- strcat(destination, blank);
- strcat(destination, c);
- printf("%s\n", destination);
- return 0;
- }
3、函数名: strchr
功 能: 在一个串中查找给定字符的第一个匹配之处\
用 法:
- char *strchr(char *str, char c);
程序例:
- #include <string.h>
- #include <stdio.h>
- int main(void)
- {
- char string[15];
- char *ptr, c = 'r';
- strcpy(string, "This is a string");
- ptr = strchr(string, c);
- if (ptr)
- printf("The character %c is at position: %d\n", c, ptr-string);
- else
- printf("The character was not found\n");
- return 0;
- }
4、函数名: strcmp
功 能: 串比较
用 法:
- int strcmp(char *str1, char *str2);
看Asic码,str1>str2,返回值 > 0;两串相等,返回0
程序例:
- #include <string.h>
- #include <stdio.h>
- int main(void)
- {
- char *buf1 = "aaa", *buf2 = "bbb", *buf3 = "ccc";
- int ptr;
- ptr = strcmp(buf2, buf1);
- if (ptr > 0)
- printf("buffer 2 is greater than buffer 1\n");
- else
- printf("buffer 2 is less than buffer 1\n");
- ptr = strcmp(buf2, buf3);
- if (ptr > 0)
- printf("buffer 2 is greater than buffer 3\n");
- else
- printf("buffer 2 is less than buffer 3\n");
- return 0;
- }
5、函数名: strncmpi
功 能: 将一个串中的一部分与另一个串比较, 不管大小写
用 法:
- int strncmpi(char *str1, char *str2, unsigned maxlen);
程序例:
- #include <string.h>
- #include <stdio.h>
- int main(void)
- {
- char *buf1 = "BBB", *buf2 = "bbb";
- int ptr;
- ptr = strcmpi(buf2, buf1);
- if (ptr > 0)
- printf("buffer 2 is greater than buffer 1\n");
- if (ptr < 0)
- printf("buffer 2 is less than buffer 1\n");
- if (ptr == 0)
- printf("buffer 2 equals buffer 1\n");
- return 0;
- }
6、函数名: strcpy
功 能: 串拷贝
用 法:
- char *strcpy(char *str1, char *str2);
程序例:
- #include <stdio.h>
- #include <string.h>
- int main(void)
- {
- char string[10];
- char *str1 = "abcdefghi";
- strcpy(string, str1);
- printf("%s\n", string);
- return 0;
- }
#p#
7、函数名: strcspn
功 能: 在串中查找第一个给定字符集内容的段
用 法:
- int strcspn(char *str1, char *str2);
程序例:
- #include <stdio.h>
- #include <string.h>
- #include <alloc.h>
- int main(void)
- {
- char *string1 = "1234567890";
- char *string2 = "747DC8";
- int length;
- length = strcspn(string1, string2);
- printf("Character where strings intersect is at position %d\n", length);
- return 0;
- }
8、函数名: strdup
功 能: 将串拷贝到新建的位置处
用 法:
- char *strdup(char *str);
程序例:
- #include <stdio.h>
- #include <string.h>
- #include <alloc.h>
- int main(void)
- {
- char *dup_str, *string = "abcde";
- dup_str = strdup(string);
- printf("%s\n", dup_str);
- free(dup_str);
- return 0;
- }
9、函数名: stricmp
功 能: 以大小写不敏感方式比较两个串
用 法:
- int stricmp(char *str1, char *str2);
程序例:
- #include <string.h>
- #include <stdio.h>
- int main(void)
- {
- char *buf1 = "BBB", *buf2 = "bbb";
- int ptr;
- ptr = stricmp(buf2, buf1);
- if (ptr > 0)
- printf("buffer 2 is greater than buffer 1\n");
- if (ptr < 0)
- printf("buffer 2 is less than buffer 1\n");
- if (ptr == 0)
- printf("buffer 2 equals buffer 1\n");
- return 0;
- }
10、函数名: strerror
功 能: 返回指向错误信息字符串的指针
用 法:
- char *strerror(int errnum);
程序例:
- #include <stdio.h>
- #include <errno.h>
- int main(void)
- {
- char *buffer;
- buffer = strerror(errno);
- printf("Error: %s\n", buffer);
- return 0;
- }
11、函数名: strcmpi
功 能: 将一个串与另一个比较, 不管大小写
用 法:
- int strcmpi(char *str1, char *str2);
程序例:
- #include <string.h>
- #include <stdio.h>
- int main(void)
- {
- char *buf1 = "BBB", *buf2 = "bbb";
- int ptr;
- ptr = strcmpi(buf2, buf1);
- if (ptr > 0)
- printf("buffer 2 is greater than buffer 1\n");
- if (ptr < 0)
- printf("buffer 2 is less than buffer 1\n");
- if (ptr == 0)
- printf("buffer 2 equals buffer 1\n");
- return 0;
- }
12、函数名: strncmp
功 能: 串比较
用 法:
- int strncmp(char *str1, char *str2, int maxlen);
程序例:
- #include <string.h>
- #include <stdio.h>
- int main(void)
- {
- char *buf1 = "aaabbb", *buf2 = "bbbccc", *buf3 = "ccc";
- int ptr;
- ptr = strncmp(buf2,buf1,3);
- if (ptr > 0)
- printf("buffer 2 is greater than buffer 1\n");
- else
- printf("buffer 2 is less than buffer 1\n");
- ptr = strncmp(buf2,buf3,3);
- if (ptr > 0)
- printf("buffer 2 is greater than buffer 3\n");
- else
- printf("buffer 2 is less than buffer 3\n");
- return(0);
- }
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