C# – Formatting Strings

Today, a topic which is mostly neglected from many of us. Here it is

Concenate strings

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Format Strings 

String.Format("Hello {0}. You are from {1}", "Ben", "Spain");

Format Numbers

String.Format("Reference Code: {0:ddd- d, MM, YYYY}, somedate);

Tue, 15, 09, 1988

Formatting Currency

String.Format("Total: {0:C}", totalamount);

5.000 €

Here is again detail information from microsoft.com

Standard numeric format strings are used to format common numeric types. A standard numeric format string takes the form Axx, where:

• A is a single alphabetic character called the format specifier. Any numeric format string that contains more than one alphabetic character, including white space, is interpreted as a custom numeric format string. For more information, see Custom Numeric Format Strings.
• xx is an optional integer called the precision specifier. The precision specifier ranges from 0 to 99 and affects the number of digits in the result. Note that the precision specifier controls the number of digits in the string representation of a number. It does not round the number itself. To perform a rounding operation, use the Math.Ceiling, Math.Floor, or Math.Round method.When precision specifier controls the number of fractional digits in the result string, the result strings reflect numbers that are rounded away from zero (that is, using MidpointRounding.AwayFromZero).

  Note

  The precision specifier determines the number of digits in the result string. To pad a result string with leading or trailing spaces, use the composite formatting feature and define an alignment component in the format item.

Standard numeric format strings are supported by:

• Some overloads of the ToString method of all numeric types. For example, you can supply a numeric format string to the Int32.ToString(String) and Int32.ToString(String, IFormatProvider)methods.
• The .NET composite formatting feature, which is used by some Write and WriteLinemethods of the Console and StreamWriter classes, the String.Format method, and the StringBuilder.AppendFormat method. The composite format feature allows you to include the string representation of multiple data items in a single string, to specify field width, and to align numbers in a field. For more information, see Composite Formatting.
• Interpolated strings in C# and Visual Basic, which provide a simplified syntax when compared to composite format strings.

The following table describes the standard numeric format specifiers and displays sample output produced by each format specifier. See the Notes section for additional information about using standard numeric format strings, and the Example section for a comprehensive illustration of their use.