带前导零和千位分隔符的格式编号

Question

I'd like to format an integer in a way that it has leading zeros and thousand separators at the same time.

I know that someInt.ToString("D6"); will give me leading zeros, but apparently it doesn't allow NumberGroupSeparator . On the other hand someInt.ToString("N"); will give me separators but no leading zeros...

Is it possible to combine both to print 123456 as 00 123 456 ? I know I can get string created with N and then manually add zeros to string in a loop or something, but maybe there's better way?

EDIT: Number of padding zeros (total digits length of number) should be adjustable.

Answer 1

If you want 00 123 456, just do:

123456.ToString("00 000 000")

If you need a fixed amount of zero's, all I can think of is this:

int NUM_LENGTH = 6;

//This is not very elegant
var NUM_STR = String.Join("", Enumerable.Range(0, NUM_LENGTH).Select((x, i) => (NUM_LENGTH - i) % 3 == 0 ? " 0" : "0"));

//But at least it works:
var example1 = 123456.ToString(NUM_STR); //Outputs  123 456
var example2 = 1234.ToString(NUM_STR); //Outputs 001 234

Answer 2

I think the following should work.

int value = 102145;
int num_length = 10; // it may change as you expected
string format = "000,000,000,000,000";
string tmp = value.ToString(format);
Console.Out.WriteLine(tmp.Substring(tmp.Length - num_length - tmp.Length/4 + 1 ));

Please let me know whether it works or not.

Corrected & working version:

int value = 102145;
int num_length = 12;
string format = "000,000,000,000,000,000";
string tmp = value.ToString(format);
int totalLength = format.Replace("000,", "000").Length;
int rem = (totalLength - num_length ) / 3;
Console.Out.WriteLine(tmp.Substring(totalLength - num_length + rem));

Answer 3

像这样的东西

 .toString("#,###");

Answer 4

You're trying to use the Standard format strings to acheive what you're after, however you're going to need to look at the Custom Numeric Format Strings (MSDN) . These should enable to set things up exactly as you require.