Convert date from Hijri Calendar to Gregorian Calendar and vise versa

////////////////////////////////////Disclaimer////////////////////////////////////////////
///This library has been wrote by : Anas Reslan Bahsas  if you are going to use it		//	
///please dont remove this line .														//					
///you have to add this class to a asp.net web project to work well.					//		//	
///I will be grateful to receive any commments or suggestion to anasbahsas@hotmail.com	//								//	
//////////////////////////////////////////////////////////////////////////////////////////
using System;
using System.Web;
using System.Diagnostics;
using System.Globalization;
using System.Data;
using System.Collections;

namespace Bahsas
{
	/// <summary>
	/// Summary description for Dates.
	/// </summary>
	public class Dates
	{
		private HttpContext cur;
		
		private const int startGreg=1900;
		private const int endGreg=2100;
		private string[] allFormats={"yyyy/MM/dd","yyyy/M/d","dd/MM/yyyy","d/M/yyyy","dd/M/yyyy","d/MM/yyyy","yyyy-MM-dd","yyyy-M-d","dd-MM-yyyy","d-M-yyyy","dd-M-yyyy","d-MM-yyyy","yyyy MM dd","yyyy M d","dd MM yyyy","d M yyyy","dd M yyyy","d MM yyyy"};
		private CultureInfo arCul;
		private CultureInfo enCul;
		private HijriCalendar h;
		private GregorianCalendar g;
			
		public Dates()
		{
			cur = HttpContext.Current;

			arCul=new CultureInfo("ar-SA");
			enCul=new CultureInfo("en-US");

			h=new  HijriCalendar();
			g=new GregorianCalendar(GregorianCalendarTypes.USEnglish);

			arCul.DateTimeFormat.Calendar=h;
			
		}
		
       	/// <summary>
		/// Check if string is hijri date and then return true 
		/// </summary>
		/// <param name="hijri"></param>
		/// <returns></returns>
		public bool IsHijri(string hijri)
		{
			if (hijri.Length<=0)
			{
				
				cur.Trace.Warn("IsHijri Error: Date String is Empty");
				return false;
			}
			try
			{	
				DateTime tempDate=DateTime.ParseExact(hijri,allFormats,arCul.DateTimeFormat,DateTimeStyles.AllowWhiteSpaces);
				if (tempDate.Year>=startGreg && tempDate.Year<=endGreg)
					return true;
				else
					return false;
			}
			catch (Exception ex)
			{
				cur.Trace.Warn("IsHijri Error :"+hijri.ToString()+"\n"+ex.Message);
				return false;
			}

		}
		/// <summary>
		/// Check if string is Gregorian date and then return true 
		/// </summary>
		/// <param name="greg"></param>
		/// <returns></returns>
		public bool IsGreg(string greg)
		{
			if (greg.Length<=0)
			{
				
				cur.Trace.Warn("IsGreg :Date String is Empty");
				return false;
			}
			try
			{	
				DateTime tempDate=DateTime.ParseExact(greg,allFormats,enCul.DateTimeFormat,DateTimeStyles.AllowWhiteSpaces);
				if (tempDate.Year>=startGreg && tempDate.Year<=endGreg)
					return true;
				else
					return false;
			}
			catch (Exception ex)
			{
				cur.Trace.Warn("IsGreg Error :"+greg.ToString()+"\n"+ex.Message);
				return false;
			}

		}

		/// <summary>
		/// Return Formatted Hijri date string 
		/// </summary>
		/// <param name="date"></param>
		/// <param name="format"></param>
		/// <returns></returns>
		public string FormatHijri(string date ,string format)
		{
			if (date.Length<=0)
			{
				
				cur.Trace.Warn("Format :Date String is Empty");
				return "";
			}
			try
			{					   
				DateTime tempDate=DateTime.ParseExact(date,allFormats,arCul.DateTimeFormat,DateTimeStyles.AllowWhiteSpaces);
				return tempDate.ToString(format,arCul.DateTimeFormat);
							
			}
			catch (Exception ex)
			{
				cur.Trace.Warn("Date :\n"+ex.Message);
				return "";
			}

		}
		/// <summary>
		/// Returned Formatted Gregorian date string
		/// </summary>
		/// <param name="date"></param>
		/// <param name="format"></param>
		/// <returns></returns>
		public string FormatGreg(string date ,string format)
		{
			if (date.Length<=0)
			{
				
				cur.Trace.Warn("Format :Date String is Empty");
				return "";
			}
			try
			{
				DateTime tempDate=DateTime.ParseExact(date,allFormats,enCul.DateTimeFormat,DateTimeStyles.AllowWhiteSpaces);
				return tempDate.ToString(format,enCul.DateTimeFormat);
							
			}
			catch (Exception ex)
			{
				cur.Trace.Warn("Date :\n"+ex.Message);
				return "";
			}

		}
		/// <summary>
		/// Return Today Gregorian date and return it in yyyy/MM/dd format
		/// </summary>
		/// <returns></returns>
		public string GDateNow()
		{
			try
			{
				return DateTime.Now.ToString("yyyy/MM/dd",enCul.DateTimeFormat);
			}
			catch (Exception ex)
			{
				cur.Trace.Warn("GDateNow :\n"+ex.Message);
				return "";
			}
		}
		/// <summary>
		/// Return formatted today Gregorian date based on your format
		/// </summary>
		/// <param name="format"></param>
		/// <returns></returns>
		public string GDateNow(string format)
		{
			try
			{
				return DateTime.Now.ToString(format,enCul.DateTimeFormat);
			}
			catch (Exception ex)
			{
				cur.Trace.Warn("GDateNow :\n"+ex.Message);
				return "";
			}
		} 
		
		/// <summary>
		/// Return Today Hijri date and return it in yyyy/MM/dd format
		/// </summary>
		/// <returns></returns>
		public string HDateNow()
		{
			try
			{
				return DateTime.Now.ToString("yyyy/MM/dd",arCul.DateTimeFormat);
			}
			catch (Exception ex)
			{
				cur.Trace.Warn("HDateNow :\n"+ex.Message);
				return "";
			}
		}
		/// <summary>
		/// Return formatted today hijri date based on your format
		/// </summary>
		/// <param name="format"></param>
		/// <returns></returns>

		public string HDateNow(string format)
		{
			try
			{
				return DateTime.Now.ToString(format,arCul.DateTimeFormat);
			}
			catch (Exception ex)
			{
				cur.Trace.Warn("HDateNow :\n"+ex.Message);
				return "";
			}
			
		}
		
		/// <summary>
		/// Convert Hijri Date to it's equivalent Gregorian Date
		/// </summary>
		/// <param name="hijri"></param>
		/// <returns></returns>
		public string HijriToGreg(string hijri)
		{
			
			if (hijri.Length<=0)
			{
				
				cur.Trace.Warn("HijriToGreg :Date String is Empty");
				return "";
			}
			try
			{
				DateTime tempDate=DateTime.ParseExact(hijri,allFormats,arCul.DateTimeFormat,DateTimeStyles.AllowWhiteSpaces);
				return tempDate.ToString("yyyy/MM/dd",enCul.DateTimeFormat);
			}
			catch (Exception ex)
			{
				cur.Trace.Warn("HijriToGreg :"+hijri.ToString()+"\n"+ex.Message);
				return "";
			}
		}
		/// <summary>
		/// Convert Hijri Date to it's equivalent Gregorian Date and return it in specified format
		/// </summary>
		/// <param name="hijri"></param>
		/// <param name="format"></param>
		/// <returns></returns>
		public string HijriToGreg(string hijri,string format)
		{
			
			if (hijri.Length<=0)
			{
				
				cur.Trace.Warn("HijriToGreg :Date String is Empty");
				return "";
			}
			try
			{
				DateTime tempDate=DateTime.ParseExact(hijri,allFormats,arCul.DateTimeFormat,DateTimeStyles.AllowWhiteSpaces);
				return tempDate.ToString(format,enCul.DateTimeFormat);
				
			}
			catch (Exception ex)
			{
				cur.Trace.Warn("HijriToGreg :"+hijri.ToString()+"\n"+ex.Message);
				return "";
			}
		}
		/// <summary>
		/// Convert Gregoian Date to it's equivalent Hijir Date
		/// </summary>
		/// <param name="greg"></param>
		/// <returns></returns>
		public string GregToHijri(string greg)
		{
			
			if (greg.Length<=0)
			{
				
				cur.Trace.Warn("GregToHijri :Date String is Empty");
				return "";
			}
			try
			{
				DateTime tempDate=DateTime.ParseExact(greg,allFormats,enCul.DateTimeFormat,DateTimeStyles.AllowWhiteSpaces);
				return tempDate.ToString("yyyy/MM/dd",arCul.DateTimeFormat);
				
			}
			catch (Exception ex)
			{
				cur.Trace.Warn("GregToHijri :"+greg.ToString()+"\n"+ex.Message);
				return "";
			}
		}
		/// <summary>
		/// Convert Hijri Date to it's equivalent Gregorian Date and return it in specified format
		/// </summary>
		/// <param name="greg"></param>
		/// <param name="format"></param>
		/// <returns></returns>
		public string GregToHijri(string greg,string format)
		{
			
			if (greg.Length<=0)
			{
				
				cur.Trace.Warn("GregToHijri :Date String is Empty");
				return "";
			}
			try
			{
				
				DateTime tempDate=DateTime.ParseExact(greg,allFormats,enCul.DateTimeFormat,DateTimeStyles.AllowWhiteSpaces);
				return tempDate.ToString(format,arCul.DateTimeFormat);
				
			}
			catch (Exception ex)
			{
				cur.Trace.Warn("GregToHijri :"+greg.ToString()+"\n"+ex.Message);
				return "";
			}
		}
		
		/// <summary>
		/// Return Gregrian Date Time as digit stamp
		/// </summary>
		/// <returns></returns>
		public string GTimeStamp()
		{
			return GDateNow("yyyyMMddHHmmss");
		}
		/// <summary>
		/// Return Hijri Date Time as digit stamp
		/// </summary>
		/// <returns></returns>
		public string HTimeStamp()
		{
			return HDateNow("yyyyMMddHHmmss");
		}

		/// <summary>
		/// Compare if the Hijri date between  other financial year and return True if within , False in not within
		/// </summary>
		/// <param name="dt">Data Table contain start date and end date ,,start date is the first column in table , end date is the second column in table</param>
		/// <param name="fromDate"></param>
		/// <param name="endDate"></param>
		/// <returns></returns>
		
		
		/// <summary>
		/// Compare two instaces of string date and return indication of thier values 
		/// </summary>
		/// <param name="d1"></param>
		/// <param name="d2"></param>
		/// <returns>positive d1 is greater than d2,negative d1 is smaller than d2, 0 both are equal</returns>
		public int Compare(string d1,string d2)
		{
			try
			{
				DateTime date1=DateTime.ParseExact(d1,allFormats,arCul.DateTimeFormat,DateTimeStyles.AllowWhiteSpaces);
				DateTime date2=DateTime.ParseExact(d2,allFormats,arCul.DateTimeFormat,DateTimeStyles.AllowWhiteSpaces);
				return DateTime.Compare(date1,date2);
			}
			catch (Exception ex)
			{
				cur.Trace.Warn("Compare :"+"\n"+ex.Message);
				return -1;
			}

		}

		
	}
}