Go语言结构
Go数组允许定义类型的变量，可容纳同类的多个数据项，但结构在Go编程，它允许结合不同种类的数据项，可使用其他用户定义的数据类型。
结构是用来代表一个记录，假设要跟踪图书馆的图书。可能要跟踪有关每本书以下属性：
-
Title(书名)
-
Author(作者)
-
Subject(科目)
-
Book ID(编号)
定义结构
定义一个结构，必须使用type和struct语句。该结构语句定义了一个新的数据类型，项目不止一个成员。类型语句是结构在我们的案例类型绑定的名称。该结构语句的格式是这样的：
type struct_variable_type struct {
member definition;
member definition;
...
member definition;
}
一旦结构类型定义，它可以被用来声明使用以下语法类型的变量。
variable_name := structure_variable_type {value1, value2...valuen}
访问结构成员
要访问结构的成员，我们使用成员访问运算符(.)。成员访问运算符是编码作为结构变量名，并且我们希望访问结构部件之间的周期。可使用struct关键字来定义结构类型的变量。以下为例子来解释结构的用法：
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 specification */
Book1.title = "Go Programming"
Book1.author = "Mahesh Kumar"
Book1.subject = "Go Programming Tutorial"
Book1.book_id = 6495407
/* book 2 specification */
Book2.title = "Telecom Billing"
Book2.author = "Zara Ali"
Book2.subject = "Telecom Billing Tutorial"
Book2.book_id = 6495700
/* print Book1 info */
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)
/* print Book2 info */
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)
}
当上述代码被编译和执行时，它产生了以下结果：
Book 1 title : Go Programming Book 1 author : Mahesh Kumar Book 1 subject : Go 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
结构作为函数参数
可以传递一个结构作为函数的参数，非常类似传递任何其他变量或指针的方式。您可以访问，就象在上面的例子已经访问的方式类似的结构变量：
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 specification */
Book1.title = "Go Programming"
Book1.author = "Mahesh Kumar"
Book1.subject = "Go Programming Tutorial"
Book1.book_id = 6495407
/* book 2 specification */
Book2.title = "Telecom Billing"
Book2.author = "Zara Ali"
Book2.subject = "Telecom Billing Tutorial"
Book2.book_id = 6495700
/* print Book1 info */
printBook(Book1)
/* print Book2 info */
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);
}
当上述代码被编译和执行时，它产生了以下结果：
Book title : Go Programming Book author : Mahesh Kumar Book subject : Go Programming Tutorial Book book_id : 6495407 Book title : Telecom Billing Book author : Zara Ali Book subject : Telecom Billing Tutorial Book book_id : 6495700
指针结构
可以非常相似定义指针结构的方式，为您定义指向任何其他变量，如下所示：
var struct_pointer *Books
现在，你可以存储结构变量的地址在上面定义的指针变量。为了找到一个结构变量的地址，使用&运算符结构在名字前，如下所示：
struct_pointer = &Book1;
要访问结构的使用指针成员的结构，您必须使用“.”运算符，如下：
struct_pointer.title;
让我们使用结构指针重新写上面的例子，希望这可以帮助您理解概念：
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 specification */
Book1.title = "Go Programming"
Book1.author = "Mahesh Kumar"
Book1.subject = "Go Programming Tutorial"
Book1.book_id = 6495407
/* book 2 specification */
Book2.title = "Telecom Billing"
Book2.author = "Zara Ali"
Book2.subject = "Telecom Billing Tutorial"
Book2.book_id = 6495700
/* print Book1 info */
printBook(&Book1)
/* print Book2 info */
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);
}
当上述代码被编译和执行时，它产生了以下结果：
Book title : Go Programming Book author : Mahesh Kumar Book subject : Go Programming Tutorial Book book_id : 6495407 Book title : Telecom Billing Book author : Zara Ali Book subject : Telecom Billing Tutorial Book book_id : 6495700
