How to pad number with leading zero with C#

Author : Prakash Pradeep Gopu
Recently I was working with a project where I was in need to format a number in such a way which can apply leading zero for particular format. That means I need to pad number in 6 digit format. So following is a table in which format I need my leading zero format.

1-> 000001

20->000020

300->000300

4000->004000

50000->05000

600000à600000

So in the above example you can see that 1 will become 000001 and 20 will become 000200 format so on. So to display an integer value in decimal format I have applied interger.Tostring(String) method where I have passed “Dn” as the value of the format parameter, where n represents the minimum length of the string. So if we pass 6 it will have padding up to 6 digits.

For better understanding create a simple console application and see how its works. Following is a code for that.

class LeadingZeros

    {

        static void Main(string[] args)

        {

            int a = 1;

            int b = 20;

            int c = 300;

            int d = 4000;

            int e = 50000;

            int f = 600000;

            Console.WriteLine(string.Format("{0} Turns to {1}", a, a.ToString("D6")));

            Console.WriteLine(string.Format("{0} Turns to {1}", b, b.ToString("D6")));

            Console.WriteLine(string.Format("{0} Turns to {1}", c, c.ToString("D6")));

            Console.WriteLine(string.Format("{0} Turns to {1}", d, d.ToString("D6")));

            Console.WriteLine(string.Format("{0} Turns to {1}", e, e.ToString("D6")));

            Console.WriteLine(string.Format("{0} Turns to {1}", f, f.ToString("D6")));

            Console.ReadLine();

        }
}

Output :