double to string conversion

Question

I am using the below code:

string.Format("{0:###,###,###,###,###.00}",12005557590928.143);

to convert the double value to string.

it gives the output as "12,005,557,590,928.10"

if I change it to

string.Format("{0:###,###,###,###,###.##}",12005557590928.143);

I get. "12,005,557,590,928.1".

How can I get the output as "12005557590928.143"?

Here is a link that will show you all the ways to use `string.Format` http://www.csharp-examples.net/string-format-double/ — MethodMan, Jan 09 '13 at 15:54

score 3 · Accepted Answer · answered Jan 09 '13 at 15:48

3

You're seeing a precision error because of the data type you're using for the number. Try using a fixed point number type (in this case, a decimal):

string.Format("{0:###,###,###,###,###.###}", 12005557590928.143m);

answered Jan 09 '13 at 15:48

Justin Niessner

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@Rotem - Interesting. MSDN used to refer to it as fixed point. They're documentation actually still says "Compared to floating-point...". – Justin Niessner Jan 09 '13 at 16:07

score 1 · Answer 2 · answered Jan 09 '13 at 15:45

1

I believe you want string.Format("{0:###,###,###,###,###.000}",12005557590928.143); (note the extra zero at the end)

answered Jan 09 '13 at 15:45

Fiona - myaccessible.website

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I don't think he wanted zeros at the end. – Jeppe Stig Nielsen Jan 09 '13 at 15:56

Jeppe Stig Nielsen · Answer 3 · 2013-01-09T15:54:40.850

1

You can use

(12005557590928.143).ToString("R")

The custom numeric format strings will never reveal more than 15 decimal digits of a System.Double. Consider using System.Decimal if you need greater precision.

If your goal is to reveal "hidden" digits of the Double, use standard numeric format strings "R" ("round-trip") or "G17" ("general" 17 digits).

edited Jan 09 '13 at 15:54

answered Jan 09 '13 at 15:46

Jeppe Stig Nielsen

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score 1 · Answer 4 · answered Jan 09 '13 at 15:47

1

Try with .ToString("R")

Console.WriteLine((12005557590928.143).ToString("R"));

Here is a DEMO.

answered Jan 09 '13 at 15:47

Soner Gönül

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score 1 · Answer 5 · edited Jan 09 '13 at 16:00

1

Console.Write(string.Format("{0:0.000}", (12005557590928.143m)));

edited Jan 09 '13 at 16:00

Soner Gönül

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answered Jan 09 '13 at 15:57

K Roobroeck

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this yields `"12005557590928.143"` what about the commas ? – MethodMan Jan 09 '13 at 16:02
Can you please explain the suffix 'm' here? – Uthistran Selvaraj Jan 10 '13 at 03:55
@UthistranS. The 'm' stands for a decimal. For more information, Jon Skeet has a very good answer on the difference between float, double and decimal on stackoverflow http://stackoverflow.com/questions/618535/what-is-the-difference-between-decimal-float-and-double-in-c – K Roobroeck Jan 10 '13 at 09:36

double to string conversion

5 Answers5