1.32. C # structure

发布时间 : 2025-10-25 13:34:41 UTC      

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In C #, structures are value type data structures. It enables a single variable to store related data of various data types. struct keyword isused to create structures.

Structures are used to represent a record. Suppose you want to keep track ofbooks in the library. You may want to track the following properties of each book:

  • Title

  • Author

  • Subject

  • Book ID

1.32.1. Define the structure #

To define a structure, you must use the struct statement. struct statement defines a new data type with multiple members for the program.

For example, you can declare as follows Book structure:

struct Books { public string title; public string author; public string subject; public int book_id; }; 

The following program demonstrates the use of structures:

Example #

using System; using System.Text; struct Books { public string title; public string author; public string subject; public int book_id; }; public class testStructure { public static void Main(string[] args) { Books Book1; /* statement Book1,type are Books */ Books Book2; /* statement Book2,type are Books */ /* book 1 explain */ Book1.title = "C Programming"; Book1.author = "Nuha Ali"; Book1.subject = "C Programming Tutorial"; Book1.book_id = 6495407; /* book 2 explain */ Book2.title = "Telecom Billing"; Book2.author = "Zara Ali"; Book2.subject = "Telecom Billing Tutorial"; Book2.book_id = 6495700; /* print Book1 information */ Console.WriteLine( "Book 1 title : {0}", Book1.title); Console.WriteLine("Book 1 author : {0}", Book1.author); Console.WriteLine("Book 1 subject : {0}", Book1.subject); Console.WriteLine("Book 1 book_id :{0}", Book1.book_id); /* print Book2 information */ Console.WriteLine("Book 2 title : {0}", Book2.title); Console.WriteLine("Book 2 author : {0}", Book2.author); Console.WriteLine("Book 2 subject : {0}", Book2.subject); Console.WriteLine("Book 2 book_id : {0}", Book2.book_id); Console.ReadKey(); } } 

When the above code is compiled and executed, it produces the following results:

Book 1 title : C Programming Book 1 author : Nuha Ali Book 1 subject : C Programming Tutorial Book 1 book_id : 6495407 Book 2 title : Telecom Billing Book 2 author : Zara Ali Book 2 subject : Telecom Billing Tutorial Book 2 book_id : 6495700 

1.32.2. Characteristics of C # structure #

You have used a simple name called Books structure of. The structure in C # is different from that in traditional C or C++. The structure in C # has the following characteristics:

  • Structures can have methods, fields, indexes, properties, operator methods, and events.

  • Structure can define a constructor, but not a destructor. However, you cannot define a no-parameter constructor for a structure. The no-parameter constructor (default) is automatically defined and cannot be changed.

  • Unlike classes, structures cannot inherit other structures or classes.

  • Structures cannot be used as the infrastructure of other structures or classes.

  • Structure can implement one or more interfaces.

  • Structure members cannot be specified as abstract virtual or protected .

  • When you use the New operator creates a structure object, the appropriate constructor is called to create the structure. Unlike classes, structures can not be used New operator can be instantiated.

  • If not used New operator, the field is assigned and the object is used only after all fields have been initialized.

1.32.3. Vs-like structure #

There are several basic differences between classes and structures:

  • The class is a reference type, and the structure is a value type.

  • Structure does not support inheritance.

  • Structure cannot declare a default constructor.

In response to the above discussion, let’s rewrite the previous example:

Example #

using System; using System.Text; struct Books { private string title; private string author; private string subject; private int book_id; public void setValues(string t, string a, string s, int id) { title = t; author = a; subject = s; book_id =id; } public void display() { Console.WriteLine("Title : {0}", title); Console.WriteLine("Author : {0}", author); Console.WriteLine("Subject : {0}", subject); Console.WriteLine("Book_id :{0}", book_id); } }; public class testStructure { public static void Main(string[] args) { Books Book1 = new Books(); /* statement Book1,type are Books */ Books Book2 = new Books(); /* statement Book2,type are Books */ /* book 1 explain */ Book1.setValues("C Programming", "Nuha Ali", "C Programming Tutorial",6495407); /* book 2 explain */ Book2.setValues("Telecom Billing", "Zara Ali", "Telecom Billing Tutorial", 6495700); /* print Book1 information */ Book1.display(); /* print Book2 information */ Book2.display(); Console.ReadKey(); } } 

When the above code is compiled and executed, it produces the following results:

Title : C Programming Author : Nuha Ali Subject : C Programming Tutorial Book_id : 6495407 Title : Telecom Billing Author : Zara Ali Subject : Telecom Billing Tutorial Book_id : 6495700 
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