Create Collection from a DataSet

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Introduction

Since I started working in WPF, I came to know about Collections. But the tricky part here is previously I was working with Dataset, so it looks like I have started learning a new technology in the data binding perspective, because the Dataset was known to me since I started learning programming but I don't know some of its capabilities/powers either. But now in the WPF world, we used to make use of collection. Now let's start why I am here to write my first article/post/tips and tricks, etc., whatever you call it.

Background

Couple of days ago, I came up with an issue to convert DataTable to Collection in my home developed application and then I started working on this simple solution (not a higher ended solution) and I hope that will help some beginners and intermediate (maybe) developers if they have the same issue.

Code

For this demo, I was using a Person class as shown below:

/// <summary>
    /// Person Class
    /// </summary>
    public class Person
    {
        private int id;
        [XmlElement("id")]
        public int ID
        {
            get { return id; }
            set { id = value; }
        }

        private string name;
        [XmlElement("name")]
        public string Name
        {
            get { return name; }
            set { name = value; }
        }

        private string address;
        [XmlElement("address")]
        public string Address
        {
            get { return address; }
            set { address = value; }
        }

        private DateTime? dob;
        [XmlElement("dob")]
        public DateTime? DateOfBirth
        {
            get { return dob; }
            set { dob = value; }
        }

        private EmpType employeeType = EmpType.Trainee;
        [XmlElement("EmpType")]
        public EmpType EmployeeType
        {
            get { return employeeType; }
            set { employeeType = value; }
        }
    }

    /// <summary>
    /// Person Collection
    /// </summary>
    [Serializable(), XmlRoot("DocumentElement"), XmlType("Person")]
    public class PersonCollection : BindingList<Person>
    {

    }

and an Extension class for DataTable below:

public static class ExtensionsEx
    {
        private static Type collectionType;
        /// <summary>
        /// Lets you convert DataTable to BindingList
        /// </summary>
        /// <typeparam name="T">Collection type</typeparam>
        /// <param name="Dt">DataTable</param>
        /// <param name="bindingList">Collection to fill up</param>
        /// <returns></returns>
        public static Collection<T> GetCollectionfromDataTable<T>
        (this DataTable Dt, Collection<T> bindingList)
        {
            try
            {
                collectionType = bindingList.GetType();
                if (ValidateDataSet<T>(Dt))
                    using (System.IO.MemoryStream xmlStream = new System.IO.MemoryStream())
                    {
                        Dt.WriteXml(xmlStream, XmlWriteMode.IgnoreSchema);

#if DEBUG
                        xmlStream.Position = 0;
                        XmlDocument xd = new XmlDocument();
                        xd.Load(xmlStream);
#endif
                        xmlStream.Position = 0;
                        using (System.Xml.XmlTextReader collectionReader = 
                                new System.Xml.XmlTextReader(xmlStream))
                        {
                            XmlSerializer serializer = new XmlSerializer(collectionType);
                            bindingList = (Collection<T>)serializer.Deserialize(collectionReader);
                        }
                    }
                return bindingList;
            }
            catch { return null; }
        }

        /// <summary>
        /// Just to validate DataTable if it has Name of the Type T.
        /// </summary>
        /// <typeparam name="T"> Type </typeparam>
        /// <param name="Dt">DataTable</param>
        /// <returns> bool </returns>
        private static bool ValidateDataSet<T>(DataTable Dt)
        {
            var s = typeof(T);
            if (collectionType == null) return false;
            if (string.IsNullOrWhiteSpace(Dt.TableName))
            {
                Dt.TableName = s.Name;
                Dt.AcceptChanges();
            }
            return true;
        }
    }

Points of Interest

If your application requires different random number sequences, invoke this constructor repeatedly with different seed values. One way to produce a unique seed value is to make it time-dependent. For example, derive the seed value from the system clock. However, the system clock might not have sufficient resolution to provide different invocations of this constructor with a different seed value (http://msdn.microsoft.com/en-us/library/vstudio/ctssatww(v=vs.100).aspx).

History

This is my first tip. Hope it helps. I will update this soon to support all kinds of data types after learning about them.