Use the following three conventions for capitalizing identifiers.

Pascal case

The first letter in the identifier and the first letter of each subsequent concatenated word are capitalized. You can use Pascal case for identifiers of three or more characters. For example:

BackColor
Camel case

The first letter of an identifier is lowercase and the first letter of each subsequent concatenated word is capitalized. For example:

backColor
Uppercase

All letters in the identifier are capitalized. Use this convention only for identifiers that consist of two or fewer letters. For example:

System.IO
System.Web.UI
You might also have to capitalize identifiers to maintain compatibility with existing, unmanaged symbol schemes, where all uppercase characters are often used for enumerations and constant values. In general, these symbols should not be visible outside of the assembly that uses them.

The following table summarizes the capitalization rules and provides examples for the different types of identifiers.

Identifier Case Example
Class Pascal AppDomain
Enum type Pascal ErrorLevel
Enum values Pascal FatalError
Event Pascal ValueChange
Exception class Pascal WebException
Note Always ends with the suffix Exception.
Read-only Static field Pascal RedValue
Interface Pascal IDisposable
Note Always begins with the prefix I.
Method Pascal ToString
Namespace Pascal System.Drawing
Parameter Camel typeName
Property Pascal BackColor
Protected instance field Camel redValue
Note Rarely used. A property is preferable to using a protected instance field.
Public instance field Pascal RedValue
Note Rarely used. A property is preferable to using a public instance field.