1 #include<stdlib.h>

 2 #include<stdio.h>

 3 #include<string.h>

1 void trim(char *strIn /*in*/, char *strOut /*in*/);

void trim(char *strIn, char *strOut){

    int i, j ;

    i = 0;

    j = strlen(strIn) - 1;

    while(strIn[i] == ' ')

        ++i;

    while(strIn[j] == ' ')

        --j;

    strncpy(strOut, strIn + i , j - i + 1);

    strOut[j - i + 1] = '\0';

}

 1 void trim(char *strIn, char *strOut){

 2

 3     char *start, *end, *temp;//定义去除空格后字符串的头尾指针和遍历指针

 4

 5     temp = strIn;

 6

 7     while (*temp == ' '){

 8         ++temp;

 9     }

10

11     start = temp; //求得头指针

12

13     temp = strIn + strlen(strIn) - 1; //得到原字符串最后一个字符的指针(不是'\0')

14

15     printf("%c\n", *temp);

16

17     while (*temp == ' '){

18         --temp;

19     }

20

21     end = temp; //求得尾指针

22

23

24     for(strIn = start; strIn <= end; ){

25         *strOut++ = *strIn++;

26     }

27

28     *strOut = '\0';

29 }

 1 void main(){

 2     char *strIn = "   ak kl  p  ";

 3

 4     char strOut[100];

 5

 6     trim(strIn, strOut);

 7

 8     printf("*%s*\n",strOut);

 9

10     system("pause");

11 }