Two ways to import an XML file with .Net Core or .Net Framework

21 November 2019

It's always the simple stuff you forget how you do. For years I've mainly been working with JSON files, so when faced with that task of reading an XML file my brain went "I can do that" followed by "actually how did I used to do that?".

So here's two different methods. They work on .Net Core and theoretically .Net Framework (my project is .Net Core and haven't checked that they do actually work on framework).

My examples are using an XML in the following format:

1<?xml version="1.0" encoding="utf-8"?>
2<jobs>
3    <job>
4        <company>Construction Co</company>
5        <sector>Construction</sector>
6        <salary>£50,000 - £60,000</salary>
7        <active>true</active>
8        <title>Recruitment Consultant - Construction Management</title>
9    </job>
10    <job>
11        <company>Medical Co</company>
12        <sector>Healthcare</sector>
13        <salary>£60,000 - £70,000</salary>
14        <active>false</active>
15        <title>Junior Doctor</title>
16    </job>
17</jobs>

Method 1: Reading an XML file as a dynamic object

The first method is to load the XML file into a dynamic object. This is cheating slightly by first using Json Convert to convert the XML document into a JSON string and then deserializing that into a dynamic object.

1using Newtonsoft.Json;
2using System;
3using System.Collections.Generic;
4using System.Dynamic;
5using System.IO;
6using System.Text;
7using System.Xml;
8using System.Xml.Linq;
9
10namespace XMLExportExample
11{
12    class Program
13    {
14        static void Main(string[] args)
15        {
16            string jobsxml = "<?xml version=\"1.0\" encoding=\"utf-8\"?><jobs>    <job><company>Construction Co</company><sector>Construction</sector><salary>£50,000 - £60,000</salary><active>true</active><title>Recruitment Consultant - Construction Management</title></job><job><company>Medical Co</company><sector>Healthcare</sector><salary>£60,000 - £70,000</salary><active>false</active><title>Junior Doctor</title></job></jobs>";
17
18            byte[] byteArray = Encoding.UTF8.GetBytes(jobsxml);
19            MemoryStream stream = new MemoryStream(byteArray);
20            XDocument xdoc = XDocument.Load(stream);
21
22            string jsonText = JsonConvert.SerializeXNode(xdoc);
23            dynamic dyn = JsonConvert.DeserializeObject<ExpandoObject>(jsonText);
24
25            foreach (dynamic job in dyn.jobs.job)
26            {
27                string company;
28                if (IsPropertyExist(job, "company"))
29                    company = job.company;
30
31                string sector;
32                if (IsPropertyExist(job, "sector"))
33                    company = job.sector;
34
35                string salary;
36                if (IsPropertyExist(job, "salary"))
37                    company = job.salary;
38
39                string active;
40                if (IsPropertyExist(job, "active"))
41                    company = job.active;
42
43                string title;
44                if (IsPropertyExist(job, "title"))
45                    company = job.title;
46
47                // A property that doesn't exist
48                string foop;
49                if (IsPropertyExist(job, "foop"))
50                    foop = job.foop;
51            }
52
53            Console.ReadLine();
54        }
55
56        public static bool IsPropertyExist(dynamic settings, string name)
57        {
58            if (settings is ExpandoObject)
59                return ((IDictionary<string, object>)settings).ContainsKey(name);
60
61            return settings.GetType().GetProperty(name) != null;
62        }
63    }
64}
65

A foreach loop then goes through each of the jobs, and a helper function IsPropertyExist checks for the existence of a value before trying to read it.

Method 2: Deserializing with XmlSerializer

My second approach is to turn the XML file into classes and then deserialize the XML file into it.

This approch requires more code, but most of it can be auto generated by visual studio for us, and we end up with strongly typed objects.

Creating the XML classes from XML

To create the classes for the XML structure:

1. Create a new class file and remove the class that gets created. i.e. Your just left with this

1using System;
2using System.Collections.Generic;
3using System.Text;
4
5namespace XMLExportExample
6{
7
8}

2. Copy the content of the XML file to your clipboard
3. Select the position in the file you want to the classes to go and then go to Edit > Paste Special > Paste XML as Classes

If your using my XML you will now have a class file that looks like this:

1using System;
2using System.Collections.Generic;
3using System.Text;
4
5namespace XMLExportExample
6{
7
8    // NOTE: Generated code may require at least .NET Framework 4.5 or .NET Core/Standard 2.0.
9    /// <remarks/>
10    [System.SerializableAttribute()]
11    [System.ComponentModel.DesignerCategoryAttribute("code")]
12    [System.Xml.Serialization.XmlTypeAttribute(AnonymousType = true)]
13    [System.Xml.Serialization.XmlRootAttribute(Namespace = "", IsNullable = false)]
14    public partial class jobs
15    {
16
17        private jobsJob[] jobField;
18
19        /// <remarks/>
20        [System.Xml.Serialization.XmlElementAttribute("job")]
21        public jobsJob[] job
22        {
23            get
24            {
25                return this.jobField;
26            }
27            set
28            {
29                this.jobField = value;
30            }
31        }
32    }
33
34    /// <remarks/>
35    [System.SerializableAttribute()]
36    [System.ComponentModel.DesignerCategoryAttribute("code")]
37    [System.Xml.Serialization.XmlTypeAttribute(AnonymousType = true)]
38    public partial class jobsJob
39    {
40
41        private string companyField;
42
43        private string sectorField;
44
45        private string salaryField;
46
47        private bool activeField;
48
49        private string titleField;
50
51        /// <remarks/>
52        public string company
53        {
54            get
55            {
56                return this.companyField;
57            }
58            set
59            {
60                this.companyField = value;
61            }
62        }
63
64        /// <remarks/>
65        public string sector
66        {
67            get
68            {
69                return this.sectorField;
70            }
71            set
72            {
73                this.sectorField = value;
74            }
75        }
76
77        /// <remarks/>
78        public string salary
79        {
80            get
81            {
82                return this.salaryField;
83            }
84            set
85            {
86                this.salaryField = value;
87            }
88        }
89
90        /// <remarks/>
91        public bool active
92        {
93            get
94            {
95                return this.activeField;
96            }
97            set
98            {
99                this.activeField = value;
100            }
101        }
102
103        /// <remarks/>
104        public string title
105        {
106            get
107            {
108                return this.titleField;
109            }
110            set
111            {
112                this.titleField = value;
113            }
114        }
115    }
116
117}

Notice that the active field was even picked up as being a bool.

Doing the Deserialization

To do the deserialization, first create an instance of XmlSerializer for the type of the object we want to deserialize too. In my case this is jobs.

1            var s = new System.Xml.Serialization.XmlSerializer(typeof(jobs));

Then call Deserialize passing in a XML Reader. I'm creating and XML reader on the stream I used in the dynamic example.

1            jobs o = (jobs)s.Deserialize(XmlReader.Create(stream));

The complete file now looks like this:

1using System;
2using System.IO;
3using System.Text;
4using System.Xml;
5
6namespace XMLExportExample
7{
8    class Program
9    {
10        static void Main(string[] args)
11        {
12            string jobsxml = "<?xml version=\"1.0\" encoding=\"utf-8\"?><jobs>    <job><company>Construction Co</company><sector>Construction</sector><salary>£50,000 - £60,000</salary><active>true</active><title>Recruitment Consultant - Construction Management</title></job><job><company>Medical Co</company><sector>Healthcare</sector><salary>£60,000 - £70,000</salary><active>false</active><title>Junior Doctor</title></job></jobs>";
13
14            byte[] byteArray = Encoding.UTF8.GetBytes(jobsxml);
15            MemoryStream stream = new MemoryStream(byteArray);
16
17            var s = new System.Xml.Serialization.XmlSerializer(typeof(jobs));
18            jobs o = (jobs)s.Deserialize(XmlReader.Create(stream));
19
20            Console.ReadLine();
21        }
22    }
23}

And thats it. Any missing nodes in your XML will just be blank rather than causing an error.