C语言 如何让数字在C中显示为两位数？
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/14617865/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
How do get numbers to display as two digits in C?
提问by Adeel Anwar
For C programming. How do i get numbers to be displayed as 00, 01, 02, 03, instead of 0, 1, 2, 3. I just need 0 before the number until 10.
对于 C 编程。我如何让数字显示为 00、01、02、03，而不是 0、1、2、3。我只需要在数字之前加 0，直到 10。
i know when your doing decimals you can do "%.2f" etc. but what about in reverse for integers?
我知道当你做小数时，你可以做“%.2f”等，但反过来整数呢？
here is what I am using...**
这是我正在使用的...**
printf("Please enter the hours: ");
scanf ("%d",&hour);
printf("Please enter the minutes: ");
scanf ("%d",&minute);
printf("Please enter the seconds: ");
scanf ("%d",&second);
printf("%d : %d : %d\n", hour, minute, second);
}
}
I need the numbers to display as 00 : 00 : 00
我需要数字显示为 00 : 00 : 00
??
??
回答by paxdiablo
You need to use %02dif you want leading zeroes padded to two spaces:
%02d如果要将前导零填充到两个空格，则需要使用：
printf ("%02d : %02d : %02d\n", hour, minute, second);
See for example the following complete program:
例如，请参阅以下完整程序：
#include <stdio.h>
int main (void) {
int hh = 3, mm = 1, ss = 4, dd = 159;
printf ("Time is %02d:%02d:%02d.%06d\n", hh, mm, ss, dd);
return 0;
}
which outputs:
输出：
Time is 03:01:04.000159
Keep in mind that the %02dmeans two characters minimumwidth so it would output 123 as123. That shouldn't be a problem if your values are valid hours, minutes and seconds, but it's worth keeping in mind because many inexperienced coders seem to make the mistake that 2 is somehow the minimum andmaximum length.
请记住，这%02d意味着两个字符的最小宽度，因此它将输出 123作为123. 如果您的值是有效的小时、分钟和秒，那应该不是问题，但值得记住，因为许多没有经验的编码员似乎犯了一个错误，即 2 不知何故是最小和最大长度。
回答by dreamlax
Use the format: %02dinstead. The 0means to pad the field using zeros and the 2means that the field is two characters wide, so for any numbers that take less than 2 characters to display, it will be padded with a 0.
使用格式：%02d代替。所述0垫装置使用零的字段和2表示该字段是两个字符宽，所以对于需要不到2个字符来显示任何数字，它将用0填充。
