Introduction

This code will help you to get the Extension method for GenericType Collection List for converting them to DataTable.

Background

You must know / may not know about extension method, but using this code class file you can use it without any changes.

Using the Code

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;

namespace coDEalers
{
    public static class Extension
    {
        public static DataTable ListToDataTable<T>(this IList<T> data, string tableName)
        {
            DataTable table = new DataTable(tableName);

            //special handling for value types and string
            if (typeof(T).IsValueType || typeof(T).Equals(typeof(string)))
            {

                DataColumn dc = new DataColumn("Value");
                table.Columns.Add(dc);
                foreach (T item in data)
                {
                    DataRow dr = table.NewRow();
                    dr[0] = item;
                    table.Rows.Add(dr);
                }
            }
            else
            {
                PropertyDescriptorCollection properties = TypeDescriptor.GetProperties(typeof(T));
                foreach (PropertyDescriptor prop in properties)
                {
                    table.Columns.Add(prop.Name, 
                    Nullable.GetUnderlyingType(prop.PropertyType) ?? prop.PropertyType);
                }
                foreach (T item in data)
                {
                    DataRow row = table.NewRow();
                    foreach (PropertyDescriptor prop in properties)
                    {
                        try
                        {
                            row[prop.Name] = prop.GetValue(item) ?? DBNull.Value;
                        }
                        catch (Exception ex)
                        {
                            row[prop.Name] = DBNull.Value;
                        }
                    }
                    table.Rows.Add(row);
                }
            }
            return table;
        }
    }
}

Points of Interest

This is an easy way for getting GenericList collection to DataTable.

Usage

DataTable dt = null;
List<StateList> stateListObj = JsonConvert.DeserializeObject<List<StateList>>(hdn_stateDetails_JSON.Value);
dt = stateListObj.ListToDataTable<StateList>("dtState");