Get a List/DataTable of Months/Years between two Dates

In this blog you will learn how to get a List/DataTable of Months/Years between two dates.

Background

There is often a need to get a List/Datatable between two supplied dates.

Two days ago I needed to make a join between two Datatables so I thought I must share it among developers.

A scenario is that there is a table named user with a registration date. What I need to do is to create a report that will display the record for the users registered every month of this year. What I did was I fetched the data from the database that is like the following.
 
Table in my database

Table A

UserId                 UserFname                 UserCreatedDate

1                                   A                                  13/08/2013
2                                   B                                  13/10/2013
3                                   C                                  13/02/2014

The fetched data was like:

Table B

Months                 NoOfUsers

0 82013                         1
1 02013                         1
0 22014                         1

Now, I need to display a report for the users registered between 01/08/2013 and 01/03/2014.

So, I created a Datatable for all the months between those dates.

For this given below.
 
Just created a class.

public class BhanuHelper
{

   public static Array GetMonths(DateTime date1, DateTime date2)
   {
      //Note - You may change the format of date as required.
      return GetDates(date1, date2).Select(x => x.ToString("MMMM yyyy")).ToArray();
   }


   public static IEnumerable<DateTime> GetDates(DateTime date1, DateTime date2)
   {
        while (date1 <= date2)
        {
             yield return date1;
             date1 = date1.AddMonths(1);
        }
        if (date1 > date2 && date1.Month==date2.Month)
        {
            // Include the last month
                yield return date1;
        }
   }
   public static DataTable ToDataTable<T>( IList<T> data)
   {
        PropertyDescriptorCollection props =
        TypeDescriptor.GetProperties(typeof(T));
        DataTable table = new DataTable();
        for (int i = 0; i < props.Count; i++)
        {
             PropertyDescriptor prop = props[i];
             table.Columns.Add(prop.Name, prop.PropertyType);
        }
        object[] values = new object[props.Count];
        foreach (T item in data)
        {
            for (int i = 0; i < values.Length; i++)
            {
                 values[i] = props[i].GetValue(item);
            }
            table.Rows.Add(values);
        }
        return table;
   }
}

Implementation of above class

BhanuHelper.ToDataTable(BhanuHelper.GetMonths(Convert.ToDateTime("First date string"),Convert.ToDateTime("second date string")));

And the output will be like below:

Table C

Months

082013
092013
102013
112013
122013
012014
022014
032014

To fulfil my requirement finally, I did like below.
 
  Now, I just did a Left Join of my two Datatables and got the desired output.

Months                   NoOfUser

082013                          1
092013                          0
102013                          1
112013                          0
122013                          0
012014                          0
022014                          1
032014                          0

I hope this article is useful for all readers, if you have any suggestion then please contact me including beginners also.