Go language structure

Go language array can store the same type of data, but in the structure, we can define different items for different data types.

Structure is composed of a series of data sets of the same type or of different types of data constituted.

Structure represents a record, such as saving a record library of books, each book has the following properties:

• Title: Title
• Author: Author
• Subject: Subject
• ID: Books ID

Definition of the structure

Structure is defined and requires the use of type struct statement. struct will define a new data type, the structure has one or more members. type name statement sets the structure. Format structure is as follows:

type struct_variable_type struct {
   member definition;
   member definition;
   ...
   member definition;
}

Once you have defined the type of structure, it can be used to declare variables, syntax is as follows:

variable_name := structure_variable_type {value1, value2...valuen}

To a structure

If you want to access a structure member, use the dot operator, the format (.):. "A structure member name."

Type variable structure using the struct keyword definitions, examples are as follows:

package main

import "fmt"

type Books struct {
   title string
   author string
   subject string
   book_id int
}

func main() {
   var Book1 Books        /* 声明 Book1 为 Books 类型 */
   var Book2 Books        /* 声明 Book2 为 Books 类型 */

   /* book 1 描述 */
   Book1.title = "Go 语言"
   Book1.author = "www.w3big.com"
   Book1.subject = "Go 语言教程"
   Book1.book_id = 6495407

   /* book 2 描述 */
   Book2.title = "Python 教程"
   Book2.author = "www.w3big.com"
   Book2.subject = "Python 语言教程"
   Book2.book_id = 6495700

   /* 打印 Book1 信息 */
   fmt.Printf( "Book 1 title : %s\n", Book1.title)
   fmt.Printf( "Book 1 author : %s\n", Book1.author)
   fmt.Printf( "Book 1 subject : %s\n", Book1.subject)
   fmt.Printf( "Book 1 book_id : %d\n", Book1.book_id)

   /* 打印 Book2 信息 */
   fmt.Printf( "Book 2 title : %s\n", Book2.title)
   fmt.Printf( "Book 2 author : %s\n", Book2.author)
   fmt.Printf( "Book 2 subject : %s\n", Book2.subject)
   fmt.Printf( "Book 2 book_id : %d\n", Book2.book_id)
}

Examples of the implementation of the above operating results as follows:

Book 1 title : Go 语言
Book 1 author : www.w3big.com
Book 1 subject : Go 语言教程
Book 1 book_id : 6495407
Book 2 title : Python 教程
Book 2 author : www.w3big.com
Book 2 subject : Python 语言教程
Book 2 book_id : 6495700

The structure as a function parameter

You can like other data types to the type of structure passed to the function as a parameter. And by way of example above to access the structure variable:

package main

import "fmt"

type Books struct {
   title string
   author string
   subject string
   book_id int
}

func main() {
   var Book1 Books        /* 声明 Book1 为 Books 类型 */
   var Book2 Books        /* 声明 Book2 为 Books 类型 */

   /* book 1 描述 */
   Book1.title = "Go 语言"
   Book1.author = "www.w3big.com"
   Book1.subject = "Go 语言教程"
   Book1.book_id = 6495407

   /* book 2 描述 */
   Book2.title = "Python 教程"
   Book2.author = "www.w3big.com"
   Book2.subject = "Python 语言教程"
   Book2.book_id = 6495700

   /* 打印 Book1 信息 */
   printBook(Book1)

   /* 打印 Book2 信息 */
   printBook(Book2)
}

func printBook( book Books ) {
   fmt.Printf( "Book title : %s\n", book.title);
   fmt.Printf( "Book author : %s\n", book.author);
   fmt.Printf( "Book subject : %s\n", book.subject);
   fmt.Printf( "Book book_id : %d\n", book.book_id);
}

Examples of the implementation of the above operating results as follows:

Book title : Go 语言
Book author : www.w3big.com
Book subject : Go 语言教程
Book book_id : 6495407
Book title : Python 教程
Book author : www.w3big.com
Book subject : Python 语言教程
Book book_id : 6495700

Structure pointer

You can define a pointer pointing to a structure similar to other pointer variable, the format is as follows:

var struct_pointer *Books

Defined above can address memory pointer variable structure variables. See structure variable address, you can place an ampersand in front of the structure variables:

struct_pointer = &Book1;

Using a pointer to a structure member of a structure, use the operator. "":

struct_pointer.title;

Let's use the structure pointer rewrite the above example, the code below:

package main

import "fmt"

type Books struct {
   title string
   author string
   subject string
   book_id int
}

func main() {
   var Book1 Books        /* Declare Book1 of type Book */
   var Book2 Books        /* Declare Book2 of type Book */

   /* book 1 描述 */
   Book1.title = "Go 语言"
   Book1.author = "www.w3big.com"
   Book1.subject = "Go 语言教程"
   Book1.book_id = 6495407

   /* book 2 描述 */
   Book2.title = "Python 教程"
   Book2.author = "www.w3big.com"
   Book2.subject = "Python 语言教程"
   Book2.book_id = 6495700

   /* 打印 Book1 信息 */
   printBook(&Book1)

   /* 打印 Book2 信息 */
   printBook(&Book2)
}
func printBook( book *Books ) {
   fmt.Printf( "Book title : %s\n", book.title);
   fmt.Printf( "Book author : %s\n", book.author);
   fmt.Printf( "Book subject : %s\n", book.subject);
   fmt.Printf( "Book book_id : %d\n", book.book_id);
}

Examples of the implementation of the above operating results as follows:

Book title : Go 语言
Book author : www.w3big.com
Book subject : Go 语言教程
Book book_id : 6495407
Book title : Python 教程
Book author : www.w3big.com
Book subject : Python 语言教程
Book book_id : 6495700