实现接口功能时结构字段未更新

Question

如果我们有如下接口：

type IRoute interface {
    AddChildren(child IRoute)
}

以下结构：

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

并实现了接口：

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

然后在我们的 main func 中，如果我们想测试它是行不通的：

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

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

这确实按预期工作：

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)

我错过了什么？ :-)

Answer 1

func (this Route) AddChildren (child globals.IRoute) 的接收者是一个值，因此您正在更改您的 Route 结构的副本。

改成func (this *Route) AddChildren (child globals.IRoute)