How to get value from a specific child element in XML using XmlReader

Question

Here is the XML

<?xml version="1.0" encoding="UTF-8"?>
<Data_Speed>
<Tech ID = "UMTS">
    <Coverage ID="Dense_Urban">
        <DownLoad_Speed>10</DownLoad_Speed>
        <Upload_Speed>20</Upload_Speed>
    </Coverage>
    <Coverage ID="Urban">
        <DownLoad_Speed>30</DownLoad_Speed>
        <Upload_Speed>40</Upload_Speed>
    </Coverage>
    <Coverage ID="SubUrban">
        <DownLoad_Speed>50</DownLoad_Speed>
        <Upload_Speed>60</Upload_Speed>
    </Coverage>
 </Tech>
<Tech ID = "UMTS900">
    <Coverage ID="Dense_Urban">
        <DownLoad_Speed>11</DownLoad_Speed>
        <Upload_Speed>12</Upload_Speed>
    </Coverage>
    <Coverage ID="Urban">
        <DownLoad_Speed>13</DownLoad_Speed>
        <Upload_Speed>14</Upload_Speed>
    </Coverage>
    <Coverage ID="SubUrban">
        <DownLoad_Speed>15</DownLoad_Speed>
        <Upload_Speed>16</Upload_Speed>
    </Coverage>
</Tech>
<Tech ID = "4G800">
    <Coverage ID="Dense_Urban">
        <DownLoad_Speed>30</DownLoad_Speed>
        <Upload_Speed>42</Upload_Speed>
    </Coverage>
    <Coverage ID="Urban">
        <DownLoad_Speed>50</DownLoad_Speed>
        <Upload_Speed>34</Upload_Speed>
    </Coverage>
    <Coverage ID="SubUrban">
        <DownLoad_Speed>45</DownLoad_Speed>
        <Upload_Speed>46</Upload_Speed>
    </Coverage>
    <Coverage ID="Rural">
        <DownLoad_Speed>47</DownLoad_Speed>
        <Upload_Speed>48</Upload_Speed>
    </Coverage>
    <Coverage ID="Variable">
        <DownLoad_Speed>15</DownLoad_Speed>
        <Upload_Speed>52</Upload_Speed>     
    </Coverage>
    <Coverage ID="Outdoor">
        <DownLoad_Speed>25</DownLoad_Speed>
        <Upload_Speed>22</Upload_Speed>
    </Coverage>
</Tech>
</Data_Speed>

So how could I get value of DownLoad_Speed> & UpLoad_Speed> element by given Coverage ID Urban> and Tech ID UMTS900>? Say, if I give tech id value = "UMTS900" and coverage id value "Urban", I'd like to have string value dwnload_speed = 13 and Upload_Speed = 14 as result.

[Click](http://stackoverflow.com/q/6442024/1997232), [click](http://stackoverflow.com/q/14207811/1997232), [click](http://stackoverflow.com/q/36913069/1997232)... — Sinatr, Jul 29 '16 at 06:57

Hari Prasad · Answer 1 · 2016-07-29T08:23:43.093

2

Using Linq to Xml

    XDocument doc = XDocument.Load(filepath);

    //ex...
    string technology = "UMTS900"; 
    string coverage = "Dense_Urban";

    var result = doc.Descendants("Tech")
        .Where(x=> (string)x.Attribute("ID") == technology)
        .Elements("Coverage")
        .Where(x=>(string)x.Attribute("ID")== coverage)
        .Select(x=> new 
                    {
                        Dowload_Speed = (string)x.Element("DownLoad_Speed"),
                        Upload_Speed = (string)x.Element("Upload_Speed")
                    });

Check this Demo

edited Jul 29 '16 at 08:23

answered Jul 29 '16 at 07:02

Hari Prasad

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Tip: you can make use of the explicit conversions to avoid the null check, e.g. `x => (string)x.Attribute("ID") == technology` – Charles Mager Jul 29 '16 at 07:30
Thanks Hari Prasad for quick response :) – Jojo Raghav Jul 29 '16 at 08:05
Can we achieve same thing using Javascript @Hari Prasad? – Jojo Raghav Aug 03 '16 at 12:50
That is an extended question, I would suggest post new question. It may confuse people reaching this post with similar problem if we include additional implementation here. Hope you understand. – Hari Prasad Aug 03 '16 at 14:05

Prasad Joshi · Answer 2 · 2016-07-29T07:07:01.413

You need to open XML document

XmlDocument _document = new XmlDocument();
byte[] bytes = File.ReadAllBytes(filePath);
string xml = Encoding.UTF8.GetString(bytes);
try
{
_document.LoadXml(xml);
}
catch (XmlException e)
{
//exception handling
}                  

var doc = (XmlDocument)_document.CloneNode(true);

XmlNode node = doc.GetElementsByTagName("your child node name");

Once you get your node then you can do necessary thing with it

score 0 · Answer 3 · answered Jul 29 '16 at 07:34

string techId = "UMTS900";
string coverageId = "SUBURBAN";
int downloadSpeed = 0;
int uploadSpeed = 0;

XmlDocument xmlDoc = new XmlDocument();
xmlDoc.Load(@"C:\....\DataSpeed.xml");
XmlNodeList techTags = xmlDoc.GetElementsByTagName("Tech");

foreach (XmlNode techTag in techTags)
{
   if (techTag.Attributes["ID"].Value.Equals(techId,StringComparison.OrdinalIgnoreCase))
   {
      XmlNodeList coverageTags = techTag.ChildNodes;
      foreach (XmlNode coverageTag in coverageTags)
      {
         if (coverageTag.Attributes["ID"].Value.Equals(coverageId, StringComparison.OrdinalIgnoreCase))
         {
            downloadSpeed =Convert.ToInt16(coverageTag.ChildNodes[0].InnerText);
            uploadSpeed = Convert.ToInt16(coverageTag.ChildNodes[1].InnerText);
            break;
          }
       }
       break;
    }
 }

    if (downloadSpeed == 0 && uploadSpeed == 0)
    {
      Console.WriteLine("Specified Tech Id and Coverage Id not found");
    }
    else
    {
      Console.WriteLine("Download Speed is {0}. Upload Speed is {1}.",downloadSpeed,uploadSpeed);
   }

jdweng · Answer 4 · 2016-07-29T09:40:35.497

Here is solution using XmlReader with xml linq

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Xml;
using System.Xml.Linq;


namespace ConsoleApplication4
{
    class Program
    {
        const string FILENAME = @"c:\temp\test.xml";
        static void Main(string[] args)
        {

            XmlReader reader = XmlReader.Create(FILENAME);
            string id = "UMTS900";
            object coverages = null;
            while (!reader.EOF)
            {
                if (reader.Name != "Tech")
                {
                    reader.ReadToFollowing("Tech");
                }
                if (!reader.EOF)
                {
                    XElement tech = (XElement)XElement.ReadFrom(reader);
                    if((string)tech.Attribute("ID") == id)
                    {
                        coverages = tech.Descendants("Coverage").Select(x => new
                        {
                            id = (string)x.Attribute("ID"),
                            downLoad_Speed = (int)x.Element("DownLoad_Speed"),
                            upLoad_Speed = (int)x.Element("Upload_Speed"),
                        }).ToList();
                        break;
                    }
                }
            }



        }
    }

}

How to get value from a specific child element in XML using XmlReader

4 Answers4