How to format a string representation of a double to show 2 fractional digits

Question

I want to print a double as string, in a way that it allways shows 2 fractional digits, even if they are "00".

The expected output is 30.00 but the actual result is 30.

class Program
{
    static void Main(string[] args)
    {            
        short a = 10;
        int b = 20;
        double d = (double)(a + b);
        Console.WriteLine(d);
        Console.ReadKey();
    }
}

You already did... done. try `d.GetType()` it will tell you `d` is a double — EpicKip, Nov 21 '17 at 13:50
why would you *want* to add a `short` and an `int` to get a `double`? absolute worst case would be a `long`, but frankly `int` will probably be fine... — Marc Gravell, Nov 21 '17 at 13:57
ts not working man!!! actually the output should come like 30.00 but instead of that it displays **** 30. — Niru, Nov 21 '17 at 14:07

Tobias Theel · Answer 1 · 2018-03-14T13:38:50.733

Update

As the problem was not the "converting" from int/short to double, but the formatting of the resulting string, when printing i updated the Answer.

There is no need to explicitly Cast/Convert an Int/Short into Double. That is implicitly done.

Implicit Cast works like shown below:

  int i = 3;
  double d = i;

Working example of your code: There is no need for an explicit cast.

class Program
{
    static void Main(string[] args)
    {            
        short a = 10;
        int b = 20;
        double d = a + b;
        Console.WriteLine( d.ToString("0.00"));
        Console.ReadKey();
    }
}

Result:

Or you could use Convert.ToDouble() Example usage:

  int i = 3;
  double x = Convert.ToDouble(i);

Have a look at this and this for further explanation.

Update 2

Thanks to Rand Random for the following hint.

You can also use d.ToString("N2"), that way you get thousand separators.

For further Information about the difference of "0.00" and "N2" have a look at this post.

could use "N2" instead of "0.00" and you will get a thousand seperator — Rand Random, Mar 14 '18 at 13:34
@RandRandom thanks for the hint. I have included that in the answer — Tobias Theel, Mar 14 '18 at 13:39

score 0 · Answer 2 · edited Mar 14 '18 at 14:31

0

Just Change this line

Console.WriteLine(d);

To this

Console.WriteLine( d.ToString("0.00"));

This should work and will get output as 30.00. It makes use of formatting the string by the given format provider.

edited Mar 14 '18 at 14:31

Tobias Theel

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answered Nov 21 '17 at 14:18

AJRakesh

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How to format a string representation of a double to show 2 fractional digits

2 Answers2

Update 2