c# - How to make InvariantCulture recognize a comma as a decimal separator?

Question

How do I parse 1,2 with Single.Parse? The reason of asking is because, when I am using CultureInfo.InvariantCulture I don't get 1.2 as I would like, but rather 12.

Shouldn't "Invariant Culture" ignore the culture?

Consider the following example:

using System;
using System.Globalization;

public class Program
{
    public static void Main()
    {
        Console.WriteLine(Single.Parse("1,2", CultureInfo.InvariantCulture));
        Console.WriteLine(Single.Parse("1.2", CultureInfo.InvariantCulture));
        float value;
        Console.WriteLine(Single.TryParse("1,2", NumberStyles.Float, CultureInfo.InvariantCulture, out value));
        Console.WriteLine(Single.TryParse("1,2", out value));
        Console.WriteLine(value);
    }
}

The output of this will be

12
1.2
False
True
12

But I was expecting:

1.2
1.2
True
True
1.2

Based on my reading of InvariantCulture I should get that result, however I am not.

Answer 1

CultureInfo.InvariantCulture uses . as a decimal separator, and , as a thousands separator. This is independent of any user settings, and independent of the string you've got, hence the name "InvariantCulture". The specific details are listed on the NumberFormatInfo.InvariantInfo MSDN page.

To use , as the decimal separator, don't use CultureInfo.InvariantCulture. Instead, use a culture that does use , as the decimal separator. There are many that would suit your needs.

Alternatively, create a custom culture based on CultureInfo.InvariantCulture. You can call its Clone method to create a copy of which you can modify the properties.