c 语言实现字符串截取

c 语言实现字符串截取

具体代码如下：

    char* StringSub(const char* string,int start,int number)

 {

          int i = 0;

     int j = 0;

     int len = strlen(string);

     char* temp;

     if(start <= 0)

     {

         printf("Start %d is too small !\n",start);

         start = 1;

     }

     else if(start>len)

     {

         printf("Start %d is too big than string length %d!\n",start,len);

         return NULL;

     }

     if(number>(len-start+1))

     {

         printf("Number %d is too big!\n",number);

         number = len - start + 1;

     }

     if(number<0)

     {

         printf("Number %d is too small!\n",number);

         number = len - start + 1;

     }

 

     temp = (char*)malloc(sizeof(char)*(number+1));

     memset(temp,0,(number+1)*sizeof(char));

 

 

     while(i != number)

         temp[i++] = string[(start-1)+j++];

     temp[number]='\0';

 

     return temp;

}