Integer formatting, padding to a given length

Question

I need to pad the output of an integer to a given length.

For example, with a length of 4 digits, the output of the integer 4 is "0004" instead of "4". How can I do this in C# 2.0?

Answer 1

Use the string.Format command.

output = String.Format("{0:0000}", intVariable); 

More details: http://msdn.microsoft.com/en-us/library/fht0f5be.aspx

Answer 2

i think it was: intVal.ToString( "####" );

but there is some useful documentation here

Answer 3

In modern .NET 5.0+ (2021 update)

int myint = 100;
string zeroPadded = $"{myint:d8}";      // "00000100"
string leftPadded = $"{myint,8}";       // "     100"
string rightPadded = $"{myint,-8}";     // "100     "