Pad a number with starting zero in .Net

问题

I have a requirement to pad all single digits numbers with a starting zero. Can some one please suggest the best method? (ex 1 -> 01, 2 -> 02, etc)

回答1:

I'd call .ToString on the numbers, providing a format string which requires two digits, as below:

int number = 1;
string paddedNumber = number.ToString("00");

If it's part of a larger string, you can use the format string within a placeholder:

string result = string.Format("{0:00} minutes remaining", number);

回答2:

number.ToString().PadLeft(2, '0')

回答3:

Assuming you're just outputing these values, not storing them

int number = 1;
Console.Writeline("{0:00}", number);

Here's a useful resource for all formats supported by .Net.

回答4:

I'm gonna add this option as an answer since I don't see it here and it can be useful as an alternative.

In VB.NET:

''2 zeroes left pad
Dim num As Integer = 1
Dim numStr2ch As String = Strings.Right("00" & num.ToString(), 2)

''4 zeroes left pad
Dim numStr4ch As String = Strings.Right("0000" & num.ToString(), 4)

''6 zeroes left pad
Dim numStr6ch As String = Strings.Right("000000" & num.ToString(), 6)

回答5:

# In PowerShell:

$year = 2013
$month = 5
$day = 8

[string] $datestamp = [string]::Format("{0:d4}{1:d2}{2:d2}", $year, $month, $day)
Write-Host "Hurray, hurray, it's $datestamp!"

来源：https://stackoverflow.com/questions/489466/pad-a-number-with-starting-zero-in-net