在Go语言中,切片中的对象

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英文:

Object inside slice in Go

问题

我正在尝试将多个对象嵌入到一个切片中,以便稍后将它们导出为JSON。JSON应该类似于这样:

[
{
"name": "Nginx",
"version": "1.9"
},
{
"name": "ircd-hybrid",
"version": "8.2"
}
]

到目前为止,我在Go中有以下结构体:

type response struct {
application []struct {
name string
version string
}
}

现在(我甚至不确定结构体是否正确),我尝试以这种方式访问它(同样,不确定是否正确):

var d response
d.application[0].name = "Nginx"
d.application[0].version = "1.9"

依此类推。然而,它没有起作用,所以我猜我在某个地方出错了。我只是不知道具体在哪里。

英文:

I am trying to embed multiple objects inside a slice, so I can later export them as JSON. The JSON should look something like this:

[
   {
       name: "Nginx"
       version: "1.9"
   },
   {
       name: ircd-hybrid"
       version: "8.2"
    }
]

So far I have this struct in Go:

type response struct {
	application []struct {
		name        string
		version     string
	}
}

Now (I'm not even sure if the struct is correct), I'm trying to access it this way (again, not sure if this is correct):

   var d response
   d[0].name = "Nginx"
   d[0].version = "1.9"

And so on and so forth. However, it is not working, so I assume I went wrong somewhere. I just don't know where.

答案1

得分: 0

你的'model'的形式(在这种情况下是Go中的结构体)不太对。你真正想要的是这样的:

type application struct {
    Name    string `json:"name"`    // 需要将这些首字母大写,这样才能导出
    Version string `json:"version"` // 否则无法进行编组
}

apps := []application{
    {Name: "Windows", Version: "10"},
}

app := application{Name: "Linux", Version: "14.2"}
apps = append(apps, app)

JSON以[开头,表示它只是一个数组,没有封闭的对象。如果有的话,你需要另一个类型,其中包含一个[]application类型的属性。要向该数组添加项,可以使用append函数或使用“复合字面量”语法初始化它。

编辑:我添加了一些注释,以便生成的JSON具有像你的示例中那样的小写名称。如果在Go中未导出属性,其他库(如encoding/json)将无法使用它。

英文:

The form of your 'model' (the struct in Go in this case) isn't quite right. You really just want this;

type application struct {
        Name        string `json:"name"`   // gotta uppercase these so they're exported 
        Version     string `json:"version"` // otherwise you can't marshal them
    }
apps := []application{
     application{Name:"Windows", Version:"10"}
}
app := application{Name:"Linux", Vesion:"14.2"}
apps = append(apps, app)

The json opens with [ meaning it is just an array, there is no enclosing object. If there were you would want another type with an application array ( []application ) property. To add items to that array you can use append or initialize it with some instance using the 'composite literal' syntax.

EDIT: I added some annotations so the json produced will have lower cased names like in your example. If a property isn't exported in Go other libraries like encoding/json won't be able to use it.

huangapple
  • 本文由 发表于 2015年7月17日 03:14:23
  • 转载请务必保留本文链接:https://go.coder-hub.com/31462642.html
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