Saturday 2 June 2012

C# Betfair API Code for identifying WIN only markets

Identifying WIN only markets on the BETFAIR API

Updated 02-JUN-2012 

As it's Derby day again I ran into the same problem as last year with this article except that the wrong market identified as WIN ONLY was the FAV SP market. One in which you bet on the favourites starting price. Therefore I have updated the BOT code for identifying a market from the Betfair API from HorseName, Racedatetime and Course alone.

If you don't know I developed the website which allows members to access UK horse trainer information everyday about their runners.

As a side line I have also developed my own AutoBOT which uses the BETFAIR Free API to place bets automatically using my own ranking system which I have developed. You can follow my tips on Twitter at @HorseRaceInfo.

One of the problems I have come across during the development of my AutoBOT is that if you have the name of the Horse, Course and time of the race and want to find the Market ID that Betfair uses to identify each race there is a costly mistake that can occur due to all the various markets that are available.

I really got hooked on racing (not betting but actually watching horse racing) when I had a bet on Workforce in the 2010 Derby.

It came from the back of the field to storm past everyone else and won the Derby in record course time and in astonishing style.

Watching him apply the same tactics in the Prix de l'Arc de Triomphe to become the champion of Europe that same year installed the racing bug and then watching Frankel win the 2000 guineas this year in such amazing style has ensured that something I used to have no interest in watching whatsoever has become a TV channel turner.

Therefore when Frankel won the St Jame's Palace Stakes this year at Royal Ascot I was happy knowing that the AutoBOT I had written had placed a WIN bet on this horse early enough to get a decent price (for what was on offer for an almost 100% guaranteed win).

However when I found out that I had actually lost this bet that my BOT had placed I spent more than a few minutes scratching my head and cursing the PC I was sat in front of. However I found out that the actual market my application had put the bet on was a special WIN market in which the winner had to win by at least 4 clear lengths. Because Frankel had won by less than a length I had lost the bet. I wanted to know why.

I was annoyed.

I was quite pissed off actually and when I looked into it I found that to place a WIN only bet on the main WIN market in Betfair is quite a pain in the arse to achieve if you don't know the Market ID upfront as there is nothing in the compressed data that is given to you to identify that the market is the main WIN market and not some special market such as the one in which I lost that bet in.

Instead all you can do is run through a series of negative tests to ensure that the market is not a PLACE market, a Reverse Forecast or a Horse A versus Horse B market.

In fact since then I have found that there are so many possible markets it can be quite a nightmare to get the right one if you don't already have the Market ID.

For example today at 15:50 there was a race at Ascot, the Betfair Summer Double First Leg International Stakes that actually had alongside the usual markets a FIVE TO BE PLACED and TEN TO BE PLACED market. This was in a race with 23 runners!

The prices were obviously minimal and you would have had to of put down a tenner to win 70p on the favourite Hawkeythenoo but it meant that my original code to identify the main WIN market required updating as it was returning these new market ID's instead of the one that I wanted.

I have outputted the code for my Betfair API Unpack class below and this is just the part of my AutoBOT that returns a Market ID when provided with the compressed string of data that Betfair provides along with the Course name, the market type (WIN or PLACE) and the Race Date and Time.

You will see that I am using LINQ to filter out my data and I am using a custom function in my WHERE clause to return a match. It is this function that is the key as it has to check all the possible Betfair Market types to rule them out when looking for the main WIN market.

If you don't use C# then LINQ is one of the cool tools that makes it such a great language as it enables you to apply SQL like queries to any type of object that extends IEnumerable.

Obviously if you don't bet or don't use Betfair you might be wondering what the heck this has to interest you and you would be right apart from this bit of code being a nice example of how to use LINQ to return a custom list that can be iterated through like any array or list of objects.

Remember: Betfair may introduce even more markets in the future and if anyone knows of any markets I have missed then please let me know as I don't want to lose any more money by accident because of some weird market Betfair decides to trade on.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace BetfairUnpack
 // This is my object that holds data about the Betfair market
 public class MarketDataType
     public int marketId;
     public string marketName;
     public string marketType;
     public string marketStatus;
     public DateTime eventDate;
     public string menuPath;
     public string eventHeirachy;
     public int betDelay;
     public int exchangeId;
     public string countryCode;
     public DateTime lastRefresh;
     public int noOfRunners;
     public int noOfWinners;
     public double totalAmountMatched;
     public bool bspMarket;
     public bool turningInPlay;

 public class UnpackMarket

     // Use my own class amd make a list object we can loop through like an array
     public List<MarketDataType> marketData;

     private string BaseDateVal = "1/1/1970";
     private string ColonCode = "&%^@"; // The substitute code for "\:"
     private int DaylightSavings = 3600000;

// This method unpacks a compressed string and returns the correct MarketID filtering by the Course, Date and Market type
     public UnpackMarket(string MarketString, string racecourse, DateTime racedatetime, string marketType)

         string[] Mdata;

    // Betfair uses it's own format and we need to split on a colon
         Mdata = MarketString.Replace(@"\:", ColonCode).Split(':');

    // get our date and time
         DateTime BaseDate = Convert.ToDateTime(BaseDateVal);

         // if we are not currently in daylight savings then set that property to 0 so we get the correct time
    // I have had instances where the correct market is not returned due to Daylight savings time
         if (!DateTime.Now.IsDaylightSavingTime())
             DaylightSavings = 0;

    // Use LINQ on our IEnumerable object to query our list of markets filtering by our custom function MatchMarket
         IEnumerable<MarketDataType> queryMarkets =
             from m in Mdata
             where !String.IsNullOrEmpty(m)
             let field = m.Split('~')
             where (MatchMarket(field[5], BaseDate.AddMilliseconds(DaylightSavings + Convert.ToDouble(field[4])), field[1], racecourse, racedatetime, marketType))
             select new MarketDataType()
                 marketId = Convert.ToInt32(field[0]),
                 marketName = field[1].Replace(ColonCode, ":"),
                 marketType = field[2],
                 marketStatus = field[3],
                 eventDate = BaseDate.AddMilliseconds(DaylightSavings + Convert.ToDouble(field[4])),
                 menuPath = field[5].Replace(ColonCode, ":"),
                 eventHeirachy = field[6],
                 betDelay = Convert.ToInt32(field[7]),
                 exchangeId = Convert.ToInt32(field[8]),
                 countryCode = field[9],
                 lastRefresh = BaseDate.AddMilliseconds(DaylightSavings + Convert.ToDouble(field[10])),
                 noOfRunners = Convert.ToInt32(field[11]),
                 noOfWinners = Convert.ToInt32(field[12]),
                 totalAmountMatched = Convert.ToDouble(field[13]),
                 bspMarket = (field[14] == "Y"),
                 turningInPlay = (field[15] == "Y")

    // convert into a nice easy to iterate list
         marketData = queryMarkets.ToList();


// return a Market if the values provided match
     private bool MatchMarket(string menuPath, DateTime eventDate, string marketName, string racecourse, DateTime racedatetime, string marketType)
         bool success = false;

    // do some cleaning as Betfair's format isn't the prettiest!
         menuPath = menuPath.Replace(ColonCode, ":");
         marketName = marketName.Trim();

         // does the path contain the market abreviation - we keep a list of Courses and their Betfair abreviation code
         if (menuPath.Contains(racecourse))
             // check the date is also in the string
             string day = racedatetime.Day.ToString();
             string month = racedatetime.ToString("MMM");

             // we don't want 15:00 matching 17:15:00 so add :00 to the end of our time
             string time = racedatetime.ToString("HH:mm:ss");

             if (menuPath.Contains(day) && menuPath.Contains(month) && eventDate.ToString().Contains(time))
                 // if no bet type supplied returned all types
                 if (String.IsNullOrEmpty(marketType))
                     success = true;
                     if (marketType == "PLACE")
                         // place bet so look for the standard To Be Placed market (change if you want specific markets e.g the 10 Place market = 10 TBP
                         if (marketName.Contains("To Be Placed"))
                             return true;
                             return false;
                     // we can only identify the main WIN market by ruling out all other possibilities if Betfair adds new markets then this
  // can cost us some severe money!
                     else if (marketType == "WIN")                                                                                                                                                                                                                                                  
      // rule out all the various PLACE markets which seem to go up to ten horses! Just look for TBP e.g 10 TBP or 5 TBP
                         if (marketName.Contains("To Be Placed") || marketName.Contains("Place Market") || marketName.Contains(" TBP"))
                             return false;
                         // ignore forecast & reverse forecast and horseA v horseB markets                            
                         else if (marketName.Contains("forecast") || marketName.Contains("reverse") || marketName.Contains(" v ") || marketName.Contains("without ") || marketName.Contains("winning stall") || marketName.Contains(" vs ") || marketName.Contains(" rfc ") || marketName.Contains(" fc ") || marketName.Contains("less than") || marketName.Contains("more than") || marketName.Contains("lengths") || marketName.Contains("winning dist") || marketName.Contains("top jockey") || marketName.Contains("dist") || marketName.Contains("finish") || marketName.Contains("isp %") || marketName.Contains("irish") || marketName.Contains("french") || marketName.Contains("welsh") || marketName.Contains("australian") || marketName.Contains("italian") || marketName.Contains("winbsp") || marketName.Contains("fav sp") || marketName.Contains("the field"))
                             return false;
                             return true;
                         // I cannot match anything!
                         return false;


         return success;

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