系统函数C字符串的实现（11）：strchr

Posted 2020-09-28 wzjhoutai

字符查找函数strchr

char *mystrchr(const char *str, const char c)
{
	char *p = NULL;
	for (char*newp = str; *newp != '\0'; newp++)
	{
		if (*newp==c)
		{
			p = newp;//一个一个的查找
			break;
		}
	}
	return p;
}
char *mystrchrdg(const char *str, const char c)
{
	if (*str!='\0')
	{
		return NULL;
	}
	else
	{
		if (*str==c)
		{
			return str;//返回指针
		}
		mystrchrdg(++str, c);//循环区域终止
	}
}
//mystrchr
void main()
{
	char *pstr1 = mystrchr("zrf is rocket", 'z');
	char *pstr2 = <span style="font-family: Arial, Helvetica, sans-serif;">mystrchrdg</span>("zrf is rocket", 'A');
	printf("pstr2=%s\n", pstr2);
	if (pstr1 == NULL)
	{
		printf("can not find");
	}
	else
	{
		printf("can  find  %p   存在此字符：%c\n", pstr1, *pstr1);
	}
	system("pause");
}