C# Linq for xml解析返回空元素

C# Linq for xml解析返回空元素,c#,xml,linq,c#-4.0,C#,Xml,Linq,C# 4.0,我的xml文件如下所示: <?xml version="1.0" encoding="utf-8"?> <roulette xmlns="Mechanical" name="Ruleta"> <params name="Mechanical Counters"> <param name="C01"> <comm>30313</comm> <command>INA</com

我的xml文件如下所示:

<?xml version="1.0" encoding="utf-8"?>
<roulette xmlns="Mechanical" name="Ruleta">
  <params name="Mechanical Counters">
    <param name="C01">
      <comm>30313</comm>
      <command>INA</command>
      <factor>5</factor>
      <index>2</index>
      <meter>0</meter>
      <player>1023</player>
      <meterstring>ml_BET</meterstring>
    </param>
    <param name="C02">
      <comm>30313</comm>
      <command>INC</command>
      <factor>5</factor>
      <index>3</index>
      <meter>0</meter>
      <player>1023</player>
      <meterstring>ml_WIN_PAYTABLE</meterstring>
    </param>
    <param name="C03">
      <comm>30313</comm>
      <command>INE</command>
      <factor>5</factor>
      <index>0</index>
      <meter>0</meter>
      <player>1023</player>
      <meterstring>ml_CRE_IN_BA + ml_CRE_IN_REM + ml_CRE_IN_KEY + ml_CRE_IN_TICKET</meterstring>
    </param>
    <param name="C04">
      <comm>30313</comm>
      <command>ING</command>
      <factor>5</factor>
      <index>1</index>
      <meter>0</meter>
      <player>1023</player>
      <meterstring>ml_CRE_OUT_KEY + ml_CRE_OUT_HANDPAY + ml_CRE_OUT_HANDPAYJP + ml_CRE_OUT_REM + ml_CRE_OUT_TICKET</meterstring>
    </param>
    <param name="Percentage">
      <factor>10</factor>
    </param>
    <param name="WaitAnswer">
      <miliseconds>2500</miliseconds>
    </param>
  </params>
</roulette>
private void radioButton1_Click(object sender, EventArgs e)
        {
            //loadamo xml dokument
            var doc = XDocument.Load("mechanical.xml");
            //preberemo prvi element števca C01 comm
            var prvi = doc.Descendants("param")
    .Where(x => (string)x.Attribute("name") == "C01")
    .Elements("comm")
    .FirstOrDefault();
            if (prvi != null) { textBox1.Text = "Je element"; } else { textBox1.Text = "ni elementa"; }


        }

问题是它没有解析出任何内容(var
prvi
为空),但它不应该解析代码。有什么问题

您的xml有一个默认名称空间
xmlns=“Mechanical”
。要访问元素,必须指定名称空间

XNamespace ns = "Mechanical";

var prvi = doc.Descendants(ns + "param")
    .Where(x => (string)x.Attribute("name") == "C01")
    .Elements(ns + "comm")
    .FirstOrDefault();
请注意,默认名称空间不会直接应用于属性


有关更多信息,请参阅。

Tnx,现在工作正常!当我查看一个xml文件时,我在哪里可以看到它有一个名称空间?谢谢你的回答和帮助,真的帮了我大忙!