Custom Datetime String Format

We need to show the date 07/03/2016 as 7th March, 2016.
Custom  Date Format like 7th March, 2016.
we want to denote the number position in an ordered sequence such as 1st, 2nd, 3rd, 4th...etc.

 Create a ASPX page and name it custom-datetime-string-format.aspx, in the page we take a Label Control and name it to lblInvoiceDateData.

Example:
custom-datetime-string-format.aspx Page

<form id="form1" runat="server">

<table>

<tr>

  <td width="100%" valign="top" align="right">

     <span style="font-family: Calibri; font-size: 18px; font-weight: bold;">

       DATE <asp:Label ID="lblInvoiceDateData" runat="server"></asp:Label>

     </span>

  </td>

</tr>

</table>

</form>

custom-datetime-string-format.aspx.cs Page

using System;

using System.Collections.Generic;

using System.Linq;

using System.Web;

using System.Web.UI;

using System.Web.UI.WebControls;

using System.Data;

public partial class Test_custom_datetime_string_format : System.Web.UI.Page

{

    protected void Page_Load(object sender, EventArgs e)

    {

        if (!Page.IsPostBack)

        {

          

            ViewState["Invoice_ID"] = 2;

            //Master Details

            FillForm();

        }

    }

    //Fill Previous data for update

    private void FillForm()

    {

        clsCustomDatetime objInv = new clsCustomDatetime();

        DataSet ds = new DataSet();

        try

        {

            objInv.Invoice_ID = Convert.ToInt32(ViewState["Invoice_ID"]);

            ds = objInv.InvoiceReport();

            if (ds.Tables[0].Rows.Count > 0)

            {

                foreach (DataRow dr in ds.Tables[0].Rows)

                {

                    //need to show the date 03/03/2012 as March 3rd,2012 etc

                    //lblInvoiceDateData.Text = dr["Invoice_Date"].ToString();

                    DateTime date = Convert.ToDateTime(dr["Invoice_Date"].ToString());

                    var formattedDate = string.Format(new MyCustomDateProvider(), "{0}", date);

                    lblInvoiceDateData.Text = formattedDate;

               }

            }

        }

        catch (Exception ex)

        {

            throw ex;

        }

        finally

        {

            ds = null;

            objInv = null;

        }

    }

    #region Start date custom format 07/03/2012 to  7th March,2012 in c#

    public class MyCustomDateProvider : IFormatProvider, ICustomFormatter

    {

        public object GetFormat(Type formatType)

        {

            if (formatType == typeof(ICustomFormatter))

                return this;

            return null;

        }

        public string Format(string format, object arg, IFormatProvider formatProvider)

        {

            if (!(arg is DateTime)) throw new NotSupportedException();

            var dt = (DateTime)arg;

            string suffix;

            if (new[] { 11, 12, 13 }.Contains(dt.Day))

            {

                suffix = "th";

            }

            else if (dt.Day % 10 == 1)

            {

                suffix = "st";

            }

            else if (dt.Day % 10 == 2)

            {

                suffix = "nd";

            }

            else if (dt.Day % 10 == 3)

            {

                suffix = "rd";

            }

            else

            {

                suffix = "th";

            }

            return string.Format("{1}{2} {0:MMMM}, {0:yyyy}", arg, dt.Day, suffix);

        }

    }

    #endregion End date custom format 07/03/2012 to 7th March,2012 in c#

}

Result

DATE 7th March, 2016