Number Formatting

C# Number Formatting

C# provides a variety of ways to format numbers to make them more readable and to present them in specific formats. This is particularly useful for displaying data to users in a human-readable form, handling currency, percentages, and custom formats.

Key Concepts

1. Standard Numeric Format Strings

C# offers predefined formats for common scenarios like currency, decimal, and percentages.

Examples

Using Standard Numeric Format Strings

• C (Currency): Formats the number as a currency value.
• D (Decimal): Formats the number as a decimal.
• E (Exponential): Formats the number in scientific notation.
• F (Fixed-point): Formats the number as a fixed-point number.
• N (Number): Formats the number with thousand separators.
• P (Percent): Formats the number as a percentage.

using System;

class Program
{
    static void Main()
    {
        double value = 1234.5678;

        Console.WriteLine(value.ToString("C"));  // Currency
        Console.WriteLine(value.ToString("D"));  // Decimal
        Console.WriteLine(value.ToString("E"));  // Exponential
        Console.WriteLine(value.ToString("F"));  // Fixed-point
        Console.WriteLine(value.ToString("N"));  // Number
        Console.WriteLine(value.ToString("P"));  // Percent
    }
}

Advanced Features

1. Custom Numeric Format Strings

You can create custom formats to fit specific needs using special format specifiers.

using System;

class Program
{
    static void Main()
    {
        double value = 1234.5678;

        // Custom formatting with "0" as a digit placeholder and "#" as an optional digit
        Console.WriteLine(value.ToString("0.00"));     // 1234.57
        Console.WriteLine(value.ToString("00000"));    // 01235
        Console.WriteLine(value.ToString("#.##"));     // 1234.57
        Console.WriteLine(value.ToString("0,0.00"));   // 1,234.57
        Console.WriteLine(value.ToString("$#,##0.00")); // $1,234.57
    }
}

2. Culture-Specific Formatting

Numeric formatting can be affected by culture settings, which control aspects like currency symbols, decimal separators, and digit grouping.

using System;
using System.Globalization;

class Program
{
    static void Main()
    {
        double value = 1234.5678;

        CultureInfo usCulture = new CultureInfo("en-US");
        CultureInfo frCulture = new CultureInfo("fr-FR");

        Console.WriteLine(value.ToString("C", usCulture)); // $1,234.57
        Console.WriteLine(value.ToString("C", frCulture)); // 1 234,57 €
    }
}

Summary

• Standard Numeric Format Strings: Common formats like currency, decimal, percentage.
• Custom Numeric Format Strings: Allows for specific, tailored number formatting.
• Culture-Specific Formatting: Adapts number formatting to different cultural settings.

C# number formatting provides powerful tools to present numerical data in a clear and user-friendly way, enhancing the readability and usability of applications.