向字符串添加零填充

Question

如何在字符串中添加"0"填充,以便我的字符串长度始终为4？

例

If input "1", 3 padding is added = 0001
If input "25", 2 padding is added = 0025
If input "301", 1 padding is added = 0301
If input "4501", 0 padding is added = 4501

Answer 1

你可以使用PadLeft

var newString = Your_String.PadLeft(4, '0');

Answer 2

myInt.ToString("D4");

Answer 3

string strvalue="11".PadRight(4, '0');

输出= 1100

string strvalue="301".PadRight(4, '0');

输出= 3010

string strvalue="11".PadLeft(4, '0');

输出= 0011

string strvalue="301".PadLeft(4, '0');

输出= 0301

Answer 4

"1".PadLeft(4, '0');

Answer 5

int num = 1;
num.ToString("0000");