sizeof和strlen的区别测试_凤凰网2013校招笔试

strlen函数是不计算'\0'在内的

sizeo运算符计算'\0'在内

代码:

char *ch1="1234567";

char ch2[]={'1','2','3','4','5','6','7','6','7'};
char ch3[]={'1','1','\0','1'};
char ch4[]="nihao";
printf("len of ch1 = %d\n",strlen(ch1));
printf("size of ch1 = %d\n\n",sizeof(ch1));ch1是一个指针，指针变量固定是4字节


printf("len of ch2 = %d\n",strlen(ch2));输出为23毫无根据，应该是因为ch2中没有'\0'截止，故输出错误ch3正确
printf("size of ch2 = %d\n\n",sizeof(ch2));


printf("len of ch3 = %d\n",strlen(ch3));  结果中显示为2，说明strlen函数是遇到'\0'即停止计算长度
printf("size of ch3 = %d\n\n",sizeof(ch3));


printf("len of ch4 = %d\n",strlen(ch4));

printf("size of ch4= %d\n",sizeof(ch4));

结果: