如何使用LINQ生成顺序属性值？

Question

我有一些xml文件的格式如下所示，或者可能略有不同

<?xml version="1.0"?>
<!DOCTYPE PARTS SYSTEM "parts.dtd">
<?xml-stylesheet type="text/css" href="xmlpartsstyle.css"?>
<PARTS>
    <TITLE>Computer Parts</TITLE>
    <ASST>
        <PART no="xs@@">
            <ITEM>Motherboard</ITEM>
            <MANUFACTURER>ASUS</MANUFACTURER>
            <MODEL ver="v-@@@@">P3B-F</MODEL>
            <COST>123.00</COST>
        </PART>
        <PART no="xs@@">
            <ITEM>Video Card</ITEM>
            <MANUFACTURER>ATI</MANUFACTURER>
            <MODEL ver="v-@@@@">All-in-Wonder Pro</MODEL>
            <COST>160.00</COST>
        </PART>
        <PART no="xs@@">
            <ITEM>Sound Card</ITEM>
            <MANUFACTURER>Creative Labs</MANUFACTURER>
            <MODEL ver="v-@@@@">Sound Blaster Live</MODEL>
            <COST>80.00</COST>
        </PART>
    </ASST>
</PARTS>

我试图以顺序的方式生成节点<PART>的属性值，即、no、和<MODEL>，即ver，从值1开始，然后从下一个<PART>节点增加+1。因此，基本上所需的输出应该如下所示

<?xml version="1.0"?>
<!DOCTYPE PARTS SYSTEM "parts.dtd">
<?xml-stylesheet type="text/css" href="xmlpartsstyle.css"?>
<PARTS>
    <TITLE>Computer Parts</TITLE>
    <ASST>
        <PART no="xs1">
            <ITEM>Motherboard</ITEM>
            <MANUFACTURER>ASUS</MANUFACTURER>
            <MODEL ver="v-1">P3B-F</MODEL>
            <COST>123.00</COST>
        </PART>
        <PART no="xs2">
            <ITEM>Video Card</ITEM>
            <MANUFACTURER>ATI</MANUFACTURER>
            <MODEL ver="v-2">All-in-Wonder Pro</MODEL>
            <COST>160.00</COST>
        </PART>
        <PART no="xs3">
            <ITEM>Sound Card</ITEM>
            <MANUFACTURER>Creative Labs</MANUFACTURER>
            <MODEL ver="v-3">Sound Blaster Live</MODEL>
            <COST>80.00</COST>
        </PART>
    </ASST>
</PARTS>

那么，使用LINQ最简单的方法是什么呢？

我试着像

string filecontent=File.ReadAllText(@"C:\Users\Desktop\12-apr.xml");
XDocument xml=XDocument.Parse(filecontent);
var parts=xml.Descendants("PART");
var models=xml.Descendants("PART").Elements("MODEL");
foreach (var part in parts)
{
    for (int i = 0; i < parts.Count(); i++)
    {
        part.Attribute("no").Value="xs"+i.ToString();
    }

}
foreach (var model in models)
{
    for (int i = 0; i < parts.Count(); i++)
    {
        model.Attribute("ver").Value="v-"+i.ToString();
    }

}
xml.Save(@"C:\Users\Desktop\12-apr.xml");
Console.ReadLine();

但这不是我想要的..。我的代码产生的输出

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE PARTS SYSTEM "parts.dtd"[]>
<?xml-stylesheet type="text/css" href="xmlpartsstyle.css"?>
<PARTS>
  <TITLE>Computer Parts</TITLE>
  <ASST>
    <PART no="xs2">
      <ITEM>Motherboard</ITEM>
      <MANUFACTURER>ASUS</MANUFACTURER>
      <MODEL ver="v-2">P3B-F</MODEL>
      <COST>123.00</COST>
    </PART>
    <PART no="xs2">
      <ITEM>Video Card</ITEM>
      <MANUFACTURER>ATI</MANUFACTURER>
      <MODEL ver="v-2">All-in-Wonder Pro</MODEL>
      <COST>160.00</COST>
    </PART>
    <PART no="xs2">
      <ITEM>Sound Card</ITEM>
      <MANUFACTURER>Creative Labs</MANUFACTURER>
      <MODEL ver="v-2">Sound Blaster Live</MODEL>
      <COST>80.00</COST>
    </PART>
  </ASST>
</PARTS>

帮助

Answer 1

你没有明显的理由有嵌套循环..。您要为每个元素设置属性多次，而不是为每个元素设置属性一次。

一旦你摆脱了嵌套的循环，这就很简单了。但是，如果将查询具体化到列表，则会更简单。下面是一个生成所需输出的完整示例：

using System;
using System.Linq;
using System.Xml.Linq;

class Test
{
    static void Main()
    {
        var xml = XDocument.Load("input.xml");
        var parts = xml.Descendants("PART").ToList();
        var models = xml.Descendants("PART").Elements("MODEL").ToList();

        for (int i = 0; i < parts.Count; i++)
        {
            parts[i].Attribute("no").Value = $"xs{i+1}";
        }

        for (int i = 0; i < models.Count; i++)
        {
            models[i].Attribute("ver").Value = $"v-{i+1}";
        }

        xml.Save("output.xml");
    }
}