实现接口函数时，Struct字段不更新 [英] Struct field not updated when implementing interface function

问题描述

如果我们有以下接口：

  type IRoute interface {
 AddChildren（child IRoute）$ 
 
 
 $ b $ p 
 $ b 
以下结构：
 
  
 < $ b $ p> 类型路由结构{
别名字符串`json：别名``
 Children [] Route`json：children，omitempty`
 Url字符串`json：url，omitempty`
} 
  

并实现了接口：



  func（This Route）AddChildren（child globals.IRoute）{
 this.Children = append（this.Children， （Route））
} 
  

然后在我们的主要函数中，如果我们想要测试这是行不通的：

  rSettings：= Route {settings，nil，/ admin / settings} 
 rSettingsContentTypesNew：= models.Route {new，nil，/ new？type& parent} 
 rSettingsContentTypesEdit：= models.Route {edit，nil，/ edit /：nodeId} 
 
 //不工作 - 没有孩子被添加
 rSettingsContentTypes.AddChildren（rSettingsContentTypesNew）
 rSettingsContentTypes.AddChildren（rSettingsContentTypesEdit）
 rSettings.AddChildren（rSettingsContentTypes）
  


$
$ b

  rSettings：= Route {settings，nil，/ b $ b 
 admin / settings} 
 rSettingsContentTypesNew：= models.Route {new，nil，/ new？type& parent} 
 rSettingsContentTypesEdit：= models.Route {edit，nil，/编辑/：nodeId} 
 
 //然而，这确实有效
 rSettingsContentTypes.Children = append（rSettingsContentTypes.Children，rSettingsContentTypesNew）
 rSettingsContentTypes.Children = append（rSettingsContentTypes.Children ，rSettingsContentTypesEdit）
 rSettings.Children = append（rSettings.Children，rSettingsContentTypes）
  

什么是我错过了？ ： 是一个值，因此您正在更改 Route 结构的副本。

更改它到 func（this * Route）AddChildren（child globals.IRoute）

If for example we have the following interface:

type IRoute interface {
    AddChildren(child IRoute)
}

The following struct:

type Route struct {
    Alias string `json:"alias"`
    Children []Route `json:"children,omitempty"`
    Url string `json:"url,omitempty"`
}

And implemented the interface:

func (this Route) AddChildren (child globals.IRoute){
    this.Children = append(this.Children, child.(Route))
}

Then in our main func, if we wanted to test this it would not work:

rSettings := Route{"settings", nil, "/admin/settings"}
rSettingsContentTypesNew := models.Route{"new", nil, "/new?type&parent"}
rSettingsContentTypesEdit := models.Route{"edit", nil, "/edit/:nodeId"}

// Does NOT work - no children is added
rSettingsContentTypes.AddChildren(rSettingsContentTypesNew)
rSettingsContentTypes.AddChildren(rSettingsContentTypesEdit)
rSettings.AddChildren(rSettingsContentTypes)

And this does work as expected:

rSettings := Route{"settings", nil, "/admin/settings"}
rSettingsContentTypesNew := models.Route{"new", nil, "/new?type&parent"}
rSettingsContentTypesEdit := models.Route{"edit", nil, "/edit/:nodeId"}

// However this does indeed work
rSettingsContentTypes.Children = append(rSettingsContentTypes.Children,rSettingsContentTypesNew)
rSettingsContentTypes.Children = append(rSettingsContentTypes.Children,rSettingsContentTypesEdit)
rSettings.Children = append(rSettings.Children,rSettingsContentTypes)

What am I missing? :-)

解决方案

The receiver of func (this Route) AddChildren (child globals.IRoute) is a value, so you are changing a copy of your Route struct.

Change it to func (this *Route) AddChildren (child globals.IRoute)

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