In C#, a structure is a value type data type. It helps you to make a single variable to hold the related data of various data types. Structures are used to represent a record.
Features of Structures
Structure members cannot be specified as abstract, virtual, or protected.
- Structures can have methods, fields, indexers, properties, operator methods and events.
- Structures can have defined constructors, but not destructors. However, you cannot define a default constructor for a structure. The default constructor is automatically defined and cannot be changed.
- Unlike classes, structures cannot inherit other structures or classes.
- Structures cannot be used as a base for other structures or classes.
- A structure can implement one or more interfaces.
- When you create a struct object using the New operator, it is created and the appropriate constructor is called. Unlike classes, structs can be instantiated without using the new operator.
- If the new operator is not used, the fields remain unassigned and the object cannot be used until all the fields are initialized.
- public struct Struct_Emp
- private string Empname;
- private int Empid;
- public string Empname
- return Empname;
- Empname = value;
- public int GetEmpid()
- return Empid;
Class Vs Structures
- classes are reference types and structs are value types
- structures do not support inheritance
- structures cannot have default constructor
When to use Structures
- When you want your type to look and feel like a primitive type.
- When you create many instances, use them briefly and then drop them. For for example, within a loop.
- The instances you create are not passed around a lot.
- When you don't want to derive from other types or let others derive from your type.
- When you want others to operate on a copy of your data (basically pass by value semantics).
When not to use Structures
The size of the struct (the sum of the sizes of its members) is large
- You create instances, put them in a collection, iterate and modify elements in the collection. This will result in many boxing/unboxing since FCL Collections operate on the system.