1.2     00000001.20
.2      00000000.20
-.2     -0000000.20
12      00000012.00
0       00000000.00
-0      00000000.00
12.555  00000012.55

{0:00000000.00;0:0000000.00;0:00000000.00}

string format = "{0:00000000.00;-0000000.00}";

Console.WriteLine(string.Format(format, 1.2));
Console.WriteLine(string.Format(format, .2));
Console.WriteLine(string.Format(format, -.2));
Console.WriteLine(string.Format(format, 12.0));
Console.WriteLine(string.Format(format, -0.0));
Console.WriteLine(string.Format(format, 12.555));

{position:postive format;negative format;zero format}

string.Format("{0:00000000.00}", 1.2)

double d = -12.365;
        string s = d.ToString("0:00000000.00");//-0:00000012.37
        string sOut = d.ToString("00000000.00")//-00000012.37

using System;
using System.Linq;
using System.Text;

namespace ConsoleApplication3
{
    class Program
    {
        static void Main(string[] args)
        {
            Func<double, string> toFixedWidth = (d) => {
                return string.Format("{0:00000000.00;-0000000.00}", d);
            };

            foreach (var d in new double[] { 1.2, 0.2, -0.2, 12, 0, -0, 12.555 })
            {
                Console.WriteLine(toFixedWidth(d));
            }
        }
    }
}

00000001,20
00000000,20
-0000000,20
00000012,00
00000000,00
00000000,00
00000012,56
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