Null checking
Extension methods are static methods which behave like instance methods. However, unlike what happens when calling an instance method on a null
reference, when an extension method is called with a null
reference, it does not throw a NullReferenceException
. This can be quite useful in some scenarios.
For example, consider the following static class:
public static class StringExtensions { public static string EmptyIfNull(this string text) { return text ?? String.Empty; } public static string NullIfEmpty(this string text) { return String.Empty == text ? null : text; } }
string nullString = null; string emptyString = nullString.EmptyIfNull();// will return "" string anotherNullString = emptyString.NullIfEmpty(); // will return null
Null checking
Table Of Contents
2
Literals
18
Regex
19
DateTime
20
Arrays
22
Enum
23
Tuples
25
GUID
26
BigInteger
28
Looping
29
Iterators
30
IEnumerable
35
Dynamic type
37
Casting
41
Interfaces
47
Methods
48
Extension Methods
52
Keywords
53
Recursion
57
Inheritance
58
Generics
62
Reflection
65
LINQ Queries
66
LINQ to XML
68
XmlDocument
69
XDocument
79
Diagnostics
80
Overflow
86
Properties
89
Events
93
Structs
94
Attributes
95
Delegates
97
Networking
102
Action Filters
103
Polymorphism
104
Immutability
105
Indexer
107
Stream
108
Timers
109
Stopwatches
110
Threading
112
Async Await
114
BackgroundWorker
117
Lock Statement
118
Yield Keyword
121
Func delegates
124
ICloneable
125
IComparable
127
Using SQLite
128
Caching
129
Code Contracts
136
Pointers
144
Hash Functions
146
Cryptography
148
C# Script
149
Runtime Compile
150
Interoperability
156
Contributors