C语言sscanf函数的总结

在处理字符串的程序当中，经常会分析字符串，从一大长串的字符串截取我们需要的数据，这如果通过自己手写函数来分析，虽然可以，但当你知道sscanf的功能，那就自己写函数分析就显得多此一举。

这些函数的使用都很简单，总结一下，等下次使用一目了然。俗话说：好记性不如烂笔头，记录下来就是效率。

以下源代码是本人测试的源文件，附带讲解注释。

[cpp] view plain copy/***************************************************** ** Name         : sscanf.c  ** Author       : gzshun ** Version      : 1.0 ** Date         : 2011-12 ** Description  : sscanf function ******************************************************/  #include <stdio.h>  #include <stdlib.h>  #include <string.h>    static void sscanf_test(void);    static void sscanf_test(void)  {      int ret;      char *string;      int  digit;      char buf1[255];      char buf2[255];      char buf3[255];      char buf4[255];        /*1.最简单的用法*/      string = "china beijing 123";      ret = sscanf(string, "%s %s %d", buf1, buf2, &digit);      printf("1.string=%s\n", string);      printf("1.ret=%d, buf1=%s, buf2=%s, digit=%d\n\n", ret, buf1, buf2, digit);      /*     **执行结果:     **1.ret=3, buf1=china, buf2=beijing, digit=123     **可以看出,sscanf的返回值是读取的参数个数     */        /*2.取指定长度的字符串*/      string = "123456789";      sscanf(string, "%5s", buf1);      printf("2.string=%s\n", string);      printf("2.buf1=%s\n\n", buf1);      /*     **执行结果:     **2.buf1=12345     */        /*3.取到指定字符为止的字符串*/      string = "123/456";      sscanf(string, "%[^/]", buf1);      printf("3.string=%s\n", string);      printf("3.buf1=%s\n\n", buf1);      /*     **执行结果:     **3.buf1=123     */        /*4.取到指定字符集为止的字符串*/      string = "123abcABC";      sscanf(string, "%[^A-Z]", buf1);      printf("4.string=%s\n", string);      printf("4.buf1=%s\n\n", buf1);      /*     **执行结果:     **4.buf1=123abc     */        /*5.取仅包含指定字符集的字符串*/      string = "0123abcABC";      sscanf(string, "%[0-9]%[a-z]%[A-Z]", buf1, buf2, buf3);      printf("5.string=%s\n", string);      printf("5.buf1=%s, buf2=%s, buf3=%s\n\n", buf1, buf2, buf3);      /*     **执行结果:     **5.buf1=123, buf2=abc, buf3=ABC     */        /*6.获取指定字符中间的字符串*/      string = "ios<android>wp7";      sscanf(string, "%*[^<]<%[^>]", buf1);      printf("6.string=%s\n", string);      printf("6.buf1=%s\n\n", buf1);      /*     **执行结果:     **6.buf1=android     */        /*7.指定要跳过的字符串*/      string = "iosVSandroid";      sscanf(string, "%[a-z]VS%[a-z]", buf1, buf2);      printf("7.string=%s\n", string);      printf("7.buf1=%s, buf2=%s\n\n", buf1, buf2);      /*     **执行结果:     **7.buf1=ios, buf2=android     */        /*8.分割以某字符隔开的字符串*/      string = "android-iphone-wp7";      /*     **字符串取道'-'为止,后面还需要跟着分隔符'-',     **起到过滤作用,有点类似于第7点     */      sscanf(string, "%[^-]-%[^-]-%[^-]", buf1, buf2, buf3);      printf("8.string=%s\n", string);      printf("8.buf1=%s, buf2=%s, buf3=%s\n\n", buf1, buf2, buf3);      /*     **执行结果:     **8.buf1=android, buf2=iphone, buf3=wp7     */        /*9.提取邮箱地址*/      string = "Email:[e-mail]";      sscanf(string, "%[^:]:%[^@]@%[^.].%s", buf1, buf2, buf3, buf4);      printf("9.string=%s\n", string);      printf("9.buf1=%s, buf2=%s, buf3=%s, buf4=%s\n\n", buf1, buf2, buf3, buf4);      /*     **执行结果:     **9.buf1=Email, buf2=beijing, buf3=sina, buf4=com.cn     */        /*10.过滤掉不想截取或不需要的字符串--补充,     **在%号后面加一*号,代表过滤这个字符串,不读取     */      string = "android iphone wp7";      sscanf(string, "%s %*s %s", buf1, buf2);      printf("10.string=%s\n", string);      printf("10.buf1=%s, buf2=%s\n\n", buf1, buf2);      /*     **执行结果:     **10.android wp7     */  }    int main(int argc, char **argv)  {      sscanf_test();            return 0;  }    /* **测试程序 **环境: **Linux ubuntu 2.6.32-24-generic-pae #39-Ubuntu SMP Wed Jul 28 07:39:26 UTC 2010 i686 GNU/Linux **gcc version 4.4.3 (Ubuntu 4.4.3-4ubuntu5) ** gzshun@ubuntu:~/c/sscanf$ gcc sscanf.c -o sscanf gzshun@ubuntu:~/c/sscanf$ ./sscanf 1.string=china beijing 123 1.ret=3, buf1=china, buf2=beijing, digit=123  2.string=123456789 2.buf1=12345  3.string=123/456 3.buf1=123  4.string=123abcABC 4.buf1=123abc  5.string=0123abcABC 5.buf1=0123, buf2=abc, buf3=ABC  6.string=ios<android>wp7 6.buf1=android  7.string=iosVSandroid 7.buf1=ios, buf2=android  8.string=android-iphone-wp7 8.buf1=android, buf2=iphone, buf3=wp7  9.string=Email:[e-mail] 9.buf1=Email, buf2=beijing, buf3=sina, buf4=com.cn  10.string=android iphone wp7 10.buf1=android, buf2=wp7 */