c#从XML中提取数据

本文关键字:提取 数据 XML | 更新日期: 2023-09-27 18:13:00

我正在尝试从URL中的XML读取天气数据。XML看起来像这样:

<weatherdata>
<location>...</location>
<credit>...</credit>
<links>...</links>
<meta>...</meta>
<sun rise="2013-05-11T04:49:22" set="2013-05-11T21:39:03"/>
<forecast>
<text>...</text>
<tabular>
<time from="2013-05-11T01:00:00" to="2013-05-11T06:00:00" period="0">
<!--
 Valid from 2013-05-11T01:00:00 to 2013-05-11T06:00:00 
-->
<symbol number="2" name="Fair" var="mf/02n.03"/>
<precipitation value="0" minvalue="0" maxvalue="0.1"/>
<!--  Valid at 2013-05-11T01:00:00  -->
<windDirection deg="173.8" code="S" name="South"/>
<windSpeed mps="4.2" name="Gentle breeze"/>
<temperature unit="celsius" value="9"/>
<pressure unit="hPa" value="1004.2"/>
</time>
</tabular>
</forecast>
<observations>...</observations>
</weatherdata>

我对XML中的预测数据感兴趣。我想要得到时间从和时间到,然后是天气数据。例如,在XML中温度是这样写的:

<temperature unit="celsius" value="9"/>

我想用这样的方式提取数据:

 string fromTime = time from(the attribute in the xml);
                     string fromTime =time to(the attribute in the xml);
                    string name = temperature(the attribute in the xml);
                    string unit =unit(the attribute in the xml);
                    int value = value(the attribute in the xml);

我创建了能够读取一切的示例代码,但我不知道如何提取我需要的数据。我现在的代码看起来像这样:

        String URLString = "http://www.yr.no/place/Norway/Oslo/Oslo/Oslo/forecast.xml";
        XmlTextReader reader = new XmlTextReader(URLString);
        while (reader.Read())
        {
            switch (reader.NodeType)
            {
                case XmlNodeType.Element: // The node is an element.
                    Console.Write("" + reader.Name);
                    while (reader.MoveToNextAttribute()) // Read the attributes.
                        Console.Write(" " + reader.Name + "='" + reader.Value + "'");
                    Console.Write("'n");
                    Console.WriteLine("------------------------------");
                    break;
                case XmlNodeType.Text: //Display the text in each element.
                    Console.WriteLine(reader.Value);
                    break;
                case XmlNodeType.EndElement: //Display the end of the element.
                    Console.Write("</" + reader.Name);
                    Console.WriteLine(">");
                    break;
            }
        }

有什么想法我可以提取天气数据和时间吗?

c#从XML中提取数据

使用LINQ to XML

XDocument X = XDocument.Load("http://www.yr.no/place/Norway/Oslo/Oslo/Oslo/forecast.xml");
var forecast = X.Element("weatherdata").Element("forecast");
var location = forecast.Descendants("location").Attributes("name").FirstOrDefault().Value;
var tempData = forecast.Element("tabular").Elements("time");
//This is what you need
var data = tempData.Select(item=>
            new{
                from = Convert.ToDateTime(item.Attribute("from").Value),
                to = Convert.ToDateTime(item.Attribute("to").Value),
                temp = item.Element("temperature").Attribute("value").Value
            });

//Or you can do a foreach if you need to
foreach (var item in tempData)
{
        DateTime from = Convert.ToDateTime(item.Attribute("from").Value);
        var temp = item.Element("temperature").Attribute("value").Value;
}

我还没有填充所有的东西。我希望你能了解如何使用它

使用System.Xml.Linq中的XElement

XElement all = XElement.Load(reader);
var values = all.Decentents("forecast").Select(fc => {
     XElement time = fc.Element("time");
     XElement temp = fc.Element("temperature");
     return new Tuple<string, string, string, string>(
                  time.Attribute("from").Value,
                  time.Attribute("to").Value,
                  temperature.Attribute("unit").Value,
                  temperature.Attribute("value").Value);});

这可以帮助您访问所需的特定节点值。希望能有所帮助!

从XML文档中获取指定的Node值