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Generic Method for Class DB table mapping


·      Code for mapping db selection to the class

using System;
using System.Collections.Generic;
using System.Data;
using System.Reflection;

namespace DataSourceLib
{
    public class DataSource
    {
        private DataSource() { }
        public DataSource(DataSet data) {
            if (data == null) { data = new DataSet(); }
            dataSet = data;
        }
        private DataSet dataSet { set; get; }


        public IList<T> GetList<T>()
        {
            List<T> list = new List<T>();
            try
            {
                DataTable dt = dataSet.Tables[0];
                foreach (DataRow dr in dt.Rows)
                {
                    T obj = (T)Activator.CreateInstance(typeof(T));
                    PropertyInfo[] propertyInfos;
                    propertyInfos = obj.GetType().GetProperties();
                    for (int i = 0; i < dataSet.Tables[0].Columns.Count; i++)
                    {
                        foreach (PropertyInfo propertyInfo in propertyInfos)
                        {
if (dt.Columns[i].ColumnName.ToLower() ==   propertyInfo.Name.ToLower())
                            {
var val = Convert.ChangeType(dr[dt.Columns[i].ColumnName], propertyInfo.PropertyType);
                            propertyInfo.SetValue(obj, val);
                            }
                        }
                    }
                    list.Add(obj);
                }
            }
            catch (Exception)
            {
                T obj = (T)Activator.CreateInstance(typeof(T));
                list.Add(obj);
            }
            return list;
        }
    }
}

·       Client code
       class Program
    {
        static void Main()
        {
            string connectionString = GetConnectionString();
            DataSet dataSet = ConnectToData(connectionString);
            DataSourceLib.DataSource dataSource = new DataSourceLib.DataSource(dataSet);
            IList< User > users = dataSource.GetList< User >();

        }
    }
    public class User
    {
        public string ClientName { get; set; }
        public int ClientCode { get; set; }
    }


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