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C# is a language in which the null object pattern can be properly implemented. This example shows animal objects that display sounds and a NullAnimal instance used in place of the C# null keyword. The null object provides consistent behaviour and prevents a runtime null reference exception that would occur if the C# null keyword were used instead.
C# 6.0 and above have ?., the null-conditional member access operator (which is also called the Elvis operator by Microsoft and is not to be confused with the general usage of the term Elvis operator, whose equivalent in C# is ??, the null coalescing operator) and ?[], the null-conditional element access operator, which performs a null-safe call of an indexer get accessor.
The null coalescing operator is a binary operator that is part of the syntax for a basic conditional expression in several programming languages, such as (in alphabetical order): C# [1] since version 2.0, [2] Dart [3] since version 1.12.0, [4] PHP since version 7.0.0, [5] Perl since version 5.10 as logical defined-or, [6] PowerShell since 7.0.0, [7] and Swift [8] as nil-coalescing operator.
In computing, a null pointer or null reference is a value saved for indicating that the pointer or reference does not refer to a valid object. Programs routinely use null pointers to represent conditions such as the end of a list of unknown length or the failure to perform some action; this use of null pointers can be compared to nullable types ...
When copied into objects, the official release boxes values from Nullable instances, so null values and null references are considered equal. The late nature of this fix caused some controversy [5], since it required core-CLR changes affecting not only .NET2, but all dependent technologies (including C#, VB, SQL Server 2005 and Visual Studio 2005).
Use the ; empty statement [14] or the {} empty block statement the same way as in the C and derivatives examples; Use the undefined or the null expression as a complete statement (an expression statement) when the previous methods are not allowed by the syntax. Alternatives, in situations where a function is required, are:
Null functions have several uses. During software development, null functions with the same names and type signatures as a planned functions are often used as stubs—that is, as non-functional placeholders that allow the incomplete body of code to be compiled and tested prior to completion of all planned features.
In computer programming, a null-terminated string is a character string stored as an array containing the characters and terminated with a null character (a character with an internal value of zero, called "NUL" in this article, not same as the glyph zero).