strncpy函数和strcpy很相似,就是字符串的拷贝,不过它是将一个字符串的前n个字符拷贝过去,如果拷贝的不包括‘\0’,则后面补上’\0’,具体实现代码如下:
#include<stdio.h>
#include<assert.h>
char *strncpy(char *dst, const char *src, size_t num)
{
char *ret = dst;
assert((*dst != NULL) && (*src != NULL));
while (num)
{
*dst++ = *src++;
num--;
}
if (*dst != '\0')
{
*dst = '\0';
}
return ret;
}
int main()
{
char *str1 = "abcdefg";
char str2[20];
int num = 0;
scanf("%d", &num);
strncpy(str2, str1, num);
printf("%s\n", str2);
system("pause");
return 0;
}