Click here to Skip to main content
Click here to Skip to main content

Convert Datatable to Collection using Generic

, 12 Jun 2011
Rate this:
Please Sign up or sign in to vote.
This is an example to Convert from a datatable to a specific type of collection using Generic
Prerequisite: using System.Reflection;
 
Sometime at the time of coding, we need to convert a DataTable to a generic list.
 
Suppose I have a DataTable which contains Employee information. Now if I want to convert this into the collection of the Employee class. For this type of requirement, there is no in-built function. We need to write our own coding. And after sometime, we got the same requirement to some other type of object, then again new coding for that specific type.
 
Instead, we can make our custom method which will work for all types of Class.
 
First, I am creating an Extension Method.
 
public static class MyExtensionClass
{
     public static List<T> ToCollection<T>(this DataTable dt)
    {
        List<T> lst = new System.Collections.Generic.List<T>();
        Type tClass = typeof(T);
        PropertyInfo[] pClass = tClass.GetProperties();
        List<DataColumn> dc = dt.Columns.Cast<DataColumn>().ToList();
        T cn;
        foreach (DataRow item in dt.Rows)
        {
            cn = (T)Activator.CreateInstance(tClass);
            foreach (PropertyInfo pc in pClass)
            {
                // Can comment try catch block. 
                try
                {
                    DataColumn d = dc.Find(c => c.ColumnName == pc.Name);
                    if (d != null)
                        pc.SetValue(cn, item[pc.Name], null);
                }
                catch
                {
                }
            }
            lst.Add(cn);
        }
        return lst;
    }
}
 
We can comment line 1 and line 2, still it will work because of the try block.
 
Here is an example.
 

Class

    public class ClassName
    {
        public string ItemCode { get; set; }
        public string Cost { get; set; }
        public override string ToString()
        {
            return "ItemCode : " + ItemCode + ", Cost : " + Cost;
        }
    }
 

DataTable

    public DataTable getTable()
    {
        DataTable dt = new DataTable();
        dt.Columns.Add(new DataColumn("ItemCode", typeof(string)));
        dt.Columns.Add(new DataColumn("Cost", typeof(string)));
        DataRow dr;
        for (int i = 0; i < 10; i++)
        {
            dr = dt.NewRow();
            dr[0] = "ItemCode" + (i + 1);
            dr[1] = "Cost" + (i + 1);
            dt.Rows.Add(dr);
        }
        return dt;
    }
 
Now we can convert this DataTable to List like that:
 
    DataTable dt = getTable();
    List<ClassName> lst = dt.ToCollection<ClassName>();
    foreach (ClassName cn in lst)
    {
        Response.Write(cn.ToString() + "<BR/>");
    }

License

This article, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

About the Author

nit_singh
Software Developer (Senior)
India India
No Biography provided

Comments and Discussions

 
GeneralMy vote of 5 PinmemberM Rayhan8-Nov-13 0:18 
QuestionThere is a generic method to do so... PinmemberAsad Ali Malik2-Jan-13 20:04 
GeneralMy vote of 5 PinmemberPravin Patil, Mumbai8-Jul-12 22:31 
GeneralReason for my vote of 5 A great time saver PinmemberRV Williams23-Aug-11 21:14 
GeneralRe: thanks Williams Pinmembernit_singh26-Aug-11 21:35 
GeneralYou can avoid the Activator.CreateInstance call by adding a ... [modified] PinmemberRichard Deeming23-Aug-11 8:30 
GeneralRe: yes right..i will modify it Pinmembernit_singh26-Aug-11 21:36 
GeneralRe: You can avoid the Activator.CreateInstance call by adding a ... PinprofessionalAdhikari Surendra28-Jul-13 1:42 
GeneralDoes your method handle DBNull.Value for all the datatypes. PinmemberMycroft Holmes14-Aug-11 19:59 
GeneralRe: yes it handles Pinmembernit_singh17-Aug-11 8:10 
Generalusefull in some cases.But there may be some performance issu... Pinmemberleopard44713-Jun-11 19:44 
GeneralRe: leopard447 - if you have any other suggetion then publicsh h... Pinmembernit_singh14-Jun-11 23:58 
GeneralRe: Nice article. @leopard447 I was also going to test the code'... PinmemberMutahar15-Jun-11 3:29 
Generalgood one PinmemberShahriar Iqbal Chowdhury16-May-11 11:41 

General General    News News    Suggestion Suggestion    Question Question    Bug Bug    Answer Answer    Joke Joke    Rant Rant    Admin Admin   

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.

| Advertise | Privacy | Mobile
Web01 | 2.8.140709.1 | Last Updated 12 Jun 2011
Article Copyright 2011 by nit_singh
Everything else Copyright © CodeProject, 1999-2014
Terms of Service
Layout: fixed | fluid