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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。

/*****************************************************
** 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:beijing@sina.com.cn";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=1232.string=123456789
2.buf1=123453.string=123/456
3.buf1=1234.string=123abcABC
4.buf1=123abc5.string=0123abcABC
5.buf1=0123, buf2=abc, buf3=ABC6.string=ios<android>wp7
6.buf1=android7.string=iosVSandroid
7.buf1=ios, buf2=android8.string=android-iphone-wp7
8.buf1=android, buf2=iphone, buf3=wp79.string=Email:beijing@sina.com.cn
9.buf1=Email, buf2=beijing, buf3=sina, buf4=com.cn10.string=android iphone wp7
10.buf1=android, buf2=wp7
*/