1

这是来自UPnP AV ContentDirectory v2 服务模板的示例DIDL-Lite XML 文档：

<?xml version="1.0" encoding="UTF-8"?>
<DIDL-Lite
 xmlns:dc="http://purl.org/dc/elements/1.1/"
 xmlns="urn:schemas-upnp-org:metadata-1-0/DIDL-Lite/"
 xmlns:upnp="urn:schemas-upnp-org:metadata-1-0/upnp/"
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xsi:schemaLocation="
   urn:schemas-upnp-org:metadata-1-0/DIDL-Lite/
    http://www.upnp.org/schemas/av/didl-lite-v2-20060531.xsd
   urn:schemas-upnp-org:metadata-1-0/upnp/
    http://www.upnp.org/schemas/av/upnp-v2-20061231.xsd">
   <item id="18" parentID="13" restricted="0">
      ...
   </item>
</DIDL-Lite>

如何使用Go 的 xml 包进行编组？进一步来说：

  1. 命名空间前缀是如何定义的，例如xmlns:dcand xmlns:upnp?
  2. 如何在一个元素上配置多个名称空间？
  3. 属性的命名空间是如何设置的，比如属性xsi上的前缀schemaLocation？

作为一个基础，我有这样的事情：

type DIDLLite struct {
    XMLName xml.Name `xml:"urn:schemas-upnp-org:metadata-1-0/DIDL-Lite/ DIDL-Lite"`
    // ??? namespace prefixes dc, upnp, xsi
    Objects []Object
}

我还发现了这个可能相关的错误。

4

1 回答 1

4

你给出的例子是编组的。我假设您的意思是问：“如何定义使用 xml.Marshal 编组的 Go 数据类型？”

package main

import (
    "encoding/xml"
    "fmt"
)

type DIDLLite struct {
    XMLName xml.Name
    DC      string   `xml:"xmlns:dc,attr"`
    UPNP    string   `xml:"xmlns:upnp,attr"`
    XSI     string   `xml:"xmlns:xsi,attr"`
    XLOC    string   `xml:"xsi:schemaLocation,attr"`
    Objects []Object `xml:"item"`
}

type Object struct {
    ID         string `xml:"id,attr"`
    Parent     string `xml:"parentID,attr"`
    Restricted string `xml:"restricted,attr"`
}

func main() {
    d := DIDLLite{
        XMLName: xml.Name{
            Space: "urn:schemas-upnp-org:metadata-1-0/DIDL-Lite/",
            Local: "DIDL-Lite",
        },
        DC:   "http://purl.org/dc/elements/1.1/",
        UPNP: "urn:schemas-upnp-org:metadata-1-0/upnp/",
        XSI:  "http://www.w3.org/2001/XMLSchema-instance",
        XLOC: `
   urn:schemas-upnp-org:metadata-1-0/DIDL-Lite/
    http://www.upnp.org/schemas/av/didl-lite-v2-20060531.xsd
   urn:schemas-upnp-org:metadata-1-0/upnp/
    http://www.upnp.org/schemas/av/upnp-v2-20061231.xsd`,
        Objects: []Object{{ID: "18", Parent: "13", Restricted: "0"}},
    }
    b, err := xml.MarshalIndent(d, "", "    ")
    if err != nil {
        fmt.Println(err)
        return
    }
    fmt.Println(string(b))
}

输出：

<DIDL-Lite xmlns="urn:schemas-upnp-org:metadata-1-0/DIDL-Lite/" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:upnp="urn:schemas-upnp-org:metadata-1-0/upnp/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="
   urn:schemas-upnp-org:metadata-1-0/DIDL-Lite/
    http://www.upnp.org/schemas/av/didl-lite-v2-20060531.xsd
   urn:schemas-upnp-org:metadata-1-0/upnp/
    http://www.upnp.org/schemas/av/upnp-v2-20061231.xsd">
    <item id="18" parentID="13" restricted="0"></item>
</DIDL-Lite>

可以很好地打印以匹配您上面的示例。xml.MarshallIndent 还有些原始。

于 2012-05-30T18:06:03.367 回答