如何在列表框中显示XML值或如何在标签上显示。

Question

以下给出的代码是从世界天气在线获取天气详情。代码工作正常，我得到变量＆＃34; WP_XMLdoc＆＃34;的天气详细信息。但问题是变量包含xml格式的值。那么如何分别得到每个值以及如何在标签或文本框上显示这些值。

public static XmlDocument WeatherAPI(string sLocation)
{
    HttpWebRequest WP_Request;
    HttpWebResponse WP_Response = null;
    XmlDocument WP_XMLdoc = null;
    string sKey = "********************"; //The API key generated by World Weather Online
    string sRequestUrl = "http://api.worldweatheronline.com/free/v1/weather.ashx?format=xml&"; //The request URL for XML format

    try
    {
        //Here we are concatenating the parameters
        WP_Request = (HttpWebRequest)WebRequest.Create(string.Format(sRequestUrl + "q=" + sLocation + "&key=" + sKey));
        WP_Request.UserAgent = @"Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US; rv:1.8.1.4) Gecko/20070515 Firefox/2.0.0.4";
        //Making the request
        WP_Response = (HttpWebResponse)WP_Request.GetResponse();
        WP_XMLdoc = new XmlDocument();
        //Assigning the response to our XML object
        WP_XMLdoc.Load(WP_Response.GetResponseStream());
    }
    catch (Exception ex)
    {
        Console.WriteLine(ex.Message);
    }
    WP_Response.Close();

    return WP_XMLdoc; // Here we get the five values from the website in xml format. Now I want   those xml values from this "WP_XMLdoc" variable to diplay on textbox or labels.

Answer 1

您可以使用的最好的是XDocument对象，它可以让您更好地控制XmlDocument。

这是我写的控制台应用程序。

您将使用的主要方法是元素（...）和后代（...）;

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

public class Program
{
    public static void Main()
    {
       var result =  WeatherAPI("London");

        // loop throw all weather instances... 
        foreach (var w in result.Descendants("weather"))
        {
            Console.WriteLine("Weather");
            Console.WriteLine("=================");
            foreach (var e in w.Elements())
            {
                Console.WriteLine(string.Format("Key {0} - Value {1}", e.Name, e.Value));
            }
        }

        // if you want to select specific element then use this.
        var currentCondition = result.Descendants("current_condition").FirstOrDefault();
        if (currentCondition != null)
        {
            Console.WriteLine("Current Condition");
            Console.WriteLine("=================");
            foreach (var e in currentCondition.Elements())
            {
                Console.WriteLine(string.Format("Key {0} - Value {1}", e.Name, e.Value));
            }
        }

        Console.ReadLine();
    }

    public static XDocument WeatherAPI(string sLocation)
    {
        HttpWebRequest webRequest;
        HttpWebResponse webResponse = null;
        XDocument xmlResult = null;
        var apiKey = "Your key"; //The API key generated by World Weather Online
        var apiEndpoint = "http://api.worldweatheronline.com/free/v1/weather.ashx?format=xml&";

        try
        {
            //Here we are concatenating the parameters
            webRequest =
                (HttpWebRequest) WebRequest.Create(string.Format(apiEndpoint + "q=" + sLocation + "&key=" + apiKey));
            webRequest.UserAgent =
                @"Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US; rv:1.8.1.4) Gecko/20070515 Firefox/2.0.0.4";
            //Making the request
            webResponse = (HttpWebResponse) webRequest.GetResponse();
            xmlResult = XDocument.Load(webResponse.GetResponseStream());
        }
        catch (Exception ex)
        {
            Console.WriteLine(ex.Message);
        }
        finally
        {
            if (webResponse != null)
            {
                webResponse.Close();
            }
        }


        return xmlResult;
            // Here we get the five values from the website in xml format. Now I want   those xml values from this "WP_XMLdoc" variable to diplay on textbox or labels.
    }
}

XML输出

<data>
  <request>
    <type>City</type>
    <query>London, United Kingdom</query>
  </request>
  <current_condition>
    <observation_time>04:53 AM</observation_time>
    <temp_C>17</temp_C>
    <temp_F>63</temp_F>
    <weatherCode>143</weatherCode>
    <weatherIconUrl><![CDATA[http://cdn.worldweatheronline.net/images/wsymbols01_png_64/wsymbol_0006_mist.png]]></weatherIconUrl>
    <weatherDesc><![CDATA[Mist]]></weatherDesc>
    <windspeedMiles>6</windspeedMiles>
    <windspeedKmph>9</windspeedKmph>
    <winddirDegree>20</winddirDegree>
    <winddir16Point>NNE</winddir16Point>
    <precipMM>0.0</precipMM>
    <humidity>94</humidity>
    <visibility>1</visibility>
    <pressure>1014</pressure>
    <cloudcover>75</cloudcover>
  </current_condition>
  <weather>
    <date>2014-09-20</date>
    <tempMaxC>22</tempMaxC>
    <tempMaxF>71</tempMaxF>
    <tempMinC>10</tempMinC>
    <tempMinF>50</tempMinF>
    <windspeedMiles>8</windspeedMiles>
    <windspeedKmph>13</windspeedKmph>
    <winddirection>N</winddirection>
    <winddir16Point>N</winddir16Point>
    <winddirDegree>350</winddirDegree>
    <weatherCode>119</weatherCode>
    <weatherIconUrl><![CDATA[http://cdn.worldweatheronline.net/images/wsymbols01_png_64/wsymbol_0003_white_cloud.png]]></weatherIconUrl>
    <weatherDesc><![CDATA[Cloudy ]]></weatherDesc>
    <precipMM>0.6</precipMM>
  </weather>
</data>

输出：

元素与后代之间有什么区别。

元素只查找那些直接后代的元素，即直接子元素。

后代发现任何级别的儿童，即儿童，孙子等......