struct->結構體

定義結構體

結構體定義須要使用 type 和 struct 語句。struct 語句定義一個新的數據類型，結構體有中一個或多個成員。type 語句設定告終構體的名稱。結構體的格式以下：

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

一旦定義告終構體類型，它就能用於變量的聲明，語法格式以下：

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

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訪問結構體成員

若是要訪問結構體成員，須要使用點號 (.) 操做符，格式爲："結構體.成員名"。

結構體類型變量使用struct關鍵字定義，實例以下：

package mainimport "fmt"type Books struct {   title string   author string   subject string   book_id int}func main() {   var Book1 Books        /* 聲明 Book1 爲 Books 類型 */   var Book2 Books        /* 聲明 Book2 爲 Books 類型 */   /* book 1 描述 */   Book1.title = "Go 語言"   Book1.author = "www.runoob.com"   Book1.subject = "Go 語言教程"   Book1.book_id = 6495407   /* book 2 描述 */   Book2.title = "Python 教程"   Book2.author = "www.runoob.com"   Book2.subject = "Python 語言教程"   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)}

以上實例執行運行結果爲：

Book 1 title : Go 語言Book 1 author : www.runoob.comBook 1 subject : Go 語言教程Book 1 book_id : 6495407Book 2 title : Python 教程Book 2 author : www.runoob.comBook 2 subject : Python 語言教程Book 2 book_id : 6495700

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結構體做爲函數參數

你能夠向其餘數據類型同樣將結構體類型做爲參數傳遞給函數。並以以上實例的方式訪問結構體變量：

package mainimport "fmt"type Books struct {   title string   author string   subject string   book_id int}func main() {   var Book1 Books        /* 聲明 Book1 爲 Books 類型 */   var Book2 Books        /* 聲明 Book2 爲 Books 類型 */   /* book 1 描述 */   Book1.title = "Go 語言"   Book1.author = "www.runoob.com"   Book1.subject = "Go 語言教程"   Book1.book_id = 6495407   /* book 2 描述 */   Book2.title = "Python 教程"   Book2.author = "www.runoob.com"   Book2.subject = "Python 語言教程"   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);}

以上實例執行運行結果爲：

Book title : Go 語言Book author : www.runoob.comBook subject : Go 語言教程Book book_id : 6495407Book title : Python 教程Book author : www.runoob.comBook subject : Python 語言教程Book book_id : 6495700

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結構體指針

你能夠定義指向結構體的指針相似於其餘指針變量，格式以下：

var struct_pointer *Books

以上定義的指針變量能夠存儲結構體變量的地址。查看結構體變量地址，能夠將 & 符號放置於結構體變量前：

struct_pointer = &Book1;

使用結構體指針訪問結構體成員，使用 "." 操做符：

struct_pointer.title;

接下來讓咱們使用結構體指針重寫以上實例，代碼以下：

package mainimport "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 語言"   Book1.author = "www.runoob.com"   Book1.subject = "Go 語言教程"   Book1.book_id = 6495407   /* book 2 描述 */   Book2.title = "Python 教程"   Book2.author = "www.runoob.com"   Book2.subject = "Python 語言教程"   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);}

以上實例執行運行結果爲：

Book title : Go 語言Book author : www.runoob.comBook subject : Go 語言教程Book book_id : 6495407Book title : Python 教程Book author : www.runoob.comBook subject : Python 語言教程Book book_id : 6495700

// struct project main.go

main

import (

    "fmt"

)

type A struct{//嵌套使用

    //B

    //C  A沒法指定B仍是C 因此C未找到

Name

}

type B struct{//嵌套使用

Name

}

func main() {//結構體要用大括號 

    //a:=A{Name:"A",B:B{Name:"B"},C:C{Name:"C"}}

    //a:=A{Name:"A",B:B{Name:"B"}}

    //fmt.Println(a.Name)//由於A的級別高於B因此輸出字符A

    //fmt.Println(a.Name,a.B.Name)

bA

bPrint

fmtPrintlnbName

cB

cPrint

fmtPrintlncName

}

b

bName

fmtPrintln

}

b

bName

fmtPrintln

}