英文:
Set fields using Reflection
问题
我正在努力解决几天来的一些 Go 语言代码问题。我有一个 Go 函数，它会在结构体内设置所有常见字段，比如 createdBy、updatedBy 等等。我已经进行了很多谷歌搜索，并得到了以下代码：
package main
import (
"fmt"
"reflect"
"time"
"strings"
)
type User struct {
UserId string `json:"userId"`
ObjectType string `json:"objectType"`
CreationDate string `json:"creationDate"`
UpdationDate string `json:"updationDate"`
Version int `json:"version"`
}
func main() {
//fmt.Println("Hello, playground")
var user = User{}
var k = setCommonParam(&user)
var p = k.(*User)
fmt.Println(p.CreationDate)
var l = *p
fmt.Println(l.ObjectType)
fmt.Println(reflect.TypeOf(k))
fmt.Println(reflect.TypeOf(user))
}
func setCommonParam(obj interface{}) interface{} {
entityValue := reflect.ValueOf(obj).Elem()
entityType := entityValue.Type()
for i:=0; i<entityValue.NumField(); i++ {
typeField := entityType.Field(i)
vField := entityValue.Field(i)
if typeField.Name == "ObjectType" {
vField.SetString(strings.ToLower(reflect.TypeOf(obj).Elem().Name()))
} else if typeField.Name == "CreationDate" {
vField.SetString(time.Now().Format(time.RFC3339))
} else if typeField.Name == "UpdationDate" {
vField.SetString(time.Now().Format(time.RFC3339))
} else if typeField.Name == "CreatedBy" {
} else if typeField.Name == "UpdatedBy" {
} else if typeField.Name == "Version" {
}
}
return obj
}
有没有办法将以下代码写成一行？
var k = setCommonParam(&user)
var p = k.(*User)
var l = *p
并像这样做：
user = setCommonParam(user)
对不起，我对此还不熟悉。谢谢。
英文:
I am struggling with some Go lang code for a few days. I have a golang function that would set all the common fields like createdBy, updatedBy, etc inside a struct. I have googled a lot and have come up with the following code.
package main
import (
"fmt"
"reflect"
"time"
"strings"
)
type User struct {
UserId string `json:"userId"`
ObjectType string `json:"objectType"`
CreationDate string `json:"creationDate"`
UpdationDate string `json:"updationDate"`
Version int `json:"version"`
}
func main() {
//fmt.Println("Hello, playground")
var user = User{}
var k = setCommonParam(&user )
var p = k.(*User)
fmt.Println(p.CreationDate)
var l = *p
fmt.Println(l.ObjectType)
fmt.Println(reflect.TypeOf(k))
fmt.Println(reflect.TypeOf(user))
}
func setCommonParam(obj interface{}) (interface{}) {
entityValue := reflect.ValueOf(obj).Elem()
entityType := entityValue.Type()
for i:=0; i<entityValue.NumField(); i++ {
typeField := entityType.Field(i)
vField := entityValue.Field(i)
if typeField.Name == "ObjectType" {
vField.SetString(strings.ToLower(reflect.TypeOf(obj).Elem().Name()))
} else if typeField.Name == "CreationDate" {
vField.SetString(time.Now().Format(time.RFC3339))
} else if typeField.Name == "UpdationDate" {
vField.SetString(time.Now().Format(time.RFC3339))
} else if typeField.Name == "CreatedBy" {
} else if typeField.Name == "UpdatedBy" {
} else if typeField.Name == "Version" {
}
}
return obj
}
Is there any way I can write the following in a single line?
var k = setCommonParam(&user )
var p = k.(*User)
var l = *p
and do something like this:
user = setCommonParam(user)
I am sorry but I am new to this. Thanks.
答案1
得分: 0
如果你的问题是“如何将这3行代码合并为一行？”，那么答案是：
var l = *(setCommonParam(&user).(*User))
英文:
If your question is "how to condense these 3 lines into one?", then the answer is:
var l = *(setCommonParam(&user).(*User))
通过集体智慧和协作来改善编程学习和解决问题的方式。致力于成为全球开发者共同参与的知识库，让每个人都能够通过互相帮助和分享经验来进步。
评论