如何在Golang中将一个对象放入另一个对象中

huangapple
go评论122阅读模式
英文:

How can i put an object in object in golang

问题

我正在尝试的是将从数据库中加载的整个对象加载到一个对象中。

  1. type RatingPK struct {
  2.     ratingsPK Rating
  3. }
  5. func (r *RatingPK) Init(rg Rating) {
  6.     r.ratingsPK = rg
  7. }    
  9. func searchUserRatings(id string)(ratings []Rating)  {
  11.     rows, err := db.Query("SELECT * FROM ratings WHERE userId = ?", id)
  13.     if err != nil {
  14.         return
  15.     }
  17.     for rows.Next() {
  19.         rate := Rating{}
  21.         err = rows.Scan(&rate.MovieId, &rate.UserId, &rate.RatingId, &rate.Rating, &rate.Timestamp)
  23.         if err != nil {
  24.             return
  25.         }
  27.         r := RatingPK{}
  28.         r.Init(rate)
  29.         ratings = append(ratings, r)
  30.     }
  32.     defer rows.Close()
  34.     return
  35. }

这段代码给我返回了以下结果：

  1. [{
  2.     "rating_id": 593,
  3.     "userId": 2,
  4.     "movieId": 93,
  5.     "rating": 3,
  6.     "timestamp": "0000-00-00"
  7. },
  8. {
  9.     "rating_id": 616,
  10.     "userId": 2,
  11.     "movieId": 94,
  12.     "rating": 3,
  13.     "timestamp": "0000-00-00"
  14. }]

现在我想做的是获取数组中的每个对象，并将其放入另一个对象中，期望的结果将是：

  1. [{"ratingsPK": {
  2.     "rating_id": 593,
  3.     "userId": 2,
  4.     "movieId": 93,
  5.     "rating": 3,
  6.     "timestamp": "0000-00-00"
  7. }},
  8. {"ratingsPK": {
  9.     "rating_id": 616,
  10.     "userId": 2,
  11.     "movieId": 94,
  12.     "rating": 3,
  13.     "timestamp": "0000-00-00"
  14. }}]

有没有办法实现这个目标？

英文:

What i am trying to do is to load an whole object coming from my database into an object.

  1. type RatingPK struct {
  2. 	ratingsPK Rating
  3. }
  5. func (r *RatingPK) Init(rg Rating) {
  6. 	r.ratingsPK = rg
  7. }    
  9. func searchUserRatings(id string)(ratings []Rating)  {
  11. 	rows, err := db.Query("SELECT * FROM ratings WHERE userId = ?", id)
  13. 	if err != nil {
  14. 		return
  15. 	}
  17. 	for rows.Next() {
  19. 		rate := Rating{}
  21. 		err = rows.Scan(&rate.MovieId, &rate.UserId, &rate.RatingId, &rate.Rating, &rate.Timestamp)
  23. 		if err != nil {
  24. 			return
  25. 		}
  27. 		r := RatingPK{}
  28. 		r.Init(rate)
  29. 		ratings = append(ratings, r)
  30. 	}
  32. 	defer rows.Close()
  34. 	return
  35. }

this code gives me this result:

  1.    [{
  2.     "rating_id": 593,
  3.     "userId": 2,
  4.     "movieId": 93,
  5.     "rating": 3,
  6.     "timestamp": "0000-00-00"
  7.   },
  8.   {
  9.     "rating_id": 616,
  10.     "userId": 2,
  11.     "movieId": 94,
  12.     "rating": 3,
  13.     "timestamp": "0000-00-00"
  14.   }]

Now what i want to do is to get each object of the array and put in to another object and the desired result will be this:

  1. [{"ratingsPK": {
  2.     "rating_id": 593,
  3.     "userId": 2,
  4.     "movieId": 93,
  5.     "rating": 3,
  6.     "timestamp": "0000-00-00"
  7.   }},
  8.   {"ratingsPK": {
  9.     "rating_id": 616,
  10.     "userId": 2,
  11.     "movieId": 94,
  12.     "rating": 3,
  13.     "timestamp": "0000-00-00"
  14.   }}]

Is there any way to achieve that?

答案1

得分: 0

你可以循环并按以下方式执行：

  1. type RatingPK struct {
  2.     ratingsPK Rating
  3. }
  5. func (r *RatingPK) Init(rg Rating) {
  6.     r.ratingsPK = rg
  7. }
  9. func searchUserRatings(id string) (ratings []RatingPK) {
  11.     rows, err := db.Query("SELECT * FROM ratings WHERE userId = ?", id)
  13.     if err != nil {
  14.         return
  15.     }
  17.     var myarray []string
  19.     for rows.Next() {
  20.         rate := Rating{}
  21.         err = rows.Scan(&rate.MovieId, &rate.UserId, &rate.RatingId, &rate.Rating, &rate.Timestamp)
  22.         if err != nil {
  23.             return
  24.         }
  25.         r := RatingPK{}
  26.         r.Init(rate)
  27.         ratings = append(ratings, r)
  28.     }
  30.     defer rows.Close()
  31.     return
  32. }
英文:

You may loop and do as follows

  1. type RatingPK struct {
  2. 	ratingsPK Rating
  3. }
  5. func (r *RatingPK) Init(rg Rating) {
  6. 	r.ratingsPK = rg
  7. }
  9. func searchUserRatings(id string) (ratings []RatingPK) {
  11. 	rows, err := db.Query("SELECT * FROM ratings WHERE userId = ?", id)
  13. 	if err != nil {
  14. 		return
  15. 	}
  17. 	var myarray []string
  19. 	for rows.Next() {
  20. 		rate := Rating{}
  21. 		err = rows.Scan(&rate.MovieId, &rate.UserId, &rate.RatingId, &rate.Rating, &rate.Timestamp)
  22. 		if err != nil {
  23. 			return
  24. 		}
  25. 		r := RatingPK{}
  26. 		r.Init(rate)
  27. 		ratings = append(ratings, r)
  28. 	}
  30. 	defer rows.Close()
  31. 	return
  32. }

答案2

得分: 0

以下是一个简短的示例，将帮助您了解如何使用嵌套结构体 如何在Golang中将一个对象放入另一个对象中

  1. package main
  3. import (
  4. 	"fmt"
  5. )
  7. type nameType struct {
  8. 	firstName string
  9. 	lastName  string
  10. }
  12. type student struct {
  13. 	name nameType
  14. 	age  int
  15. }
  17. func main() {
  18. 	bob := student{nameType{"bob", "dope"}, 18}
  20. 	fmt.Println(bob.name.firstName)
  21. }

您可以在此处进行测试 如何在Golang中将一个对象放入另一个对象中

https://play.golang.org/p/ft9PGrlrrx

英文:

Here's a short example that will help you understand how to use nested structs 如何在Golang中将一个对象放入另一个对象中

  1. package main
  3. import (
  4. 	"fmt"
  5. )
  7. type nameType struct {
  8. 	firstName string
  9. 	lastName string
  10. }
  12. type student struct {
  13. 	name nameType
  14. 	age int
  15. }
  17. func main() {
  18. 	bob := student{nameType{"bob", "dope"}, 18}
  19. 	
  20. 	fmt.Println(bob.name.firstName)
  21. }

You can test it up here 如何在Golang中将一个对象放入另一个对象中

https://play.golang.org/p/ft9PGrlrrx

huangapple
  • 本文由 发表于 2017年2月5日 01:18:53
  • 转载请务必保留本文链接：https://go.coder-hub.com/42043219.html
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