Array Sequence Validation

Question

Below I have an array Im trying to come up with a unique linq or unique slick way to do this to validate My State Field or State Array. The correct sequence is On/Off  On/Off. The last entry must always be an Off. The sequence can not be an Off/Off Off/On On/On. If my array has an invalid entry I want to do something. Can someone assist me. Correct Array Below: TStamp State 1:05 On 1:10 Off 1:15 On 1:20 Off 1:25 On 1:30 Off Wrong Array Below: TStamp State 1:05 On 1:10 On 1:15 On 1:20 Off 1:25 On 1:30 Off

Vulpes · Answer

The following uses regular expressions rather than LINQ though it's the not the usual way one would validate such a sequence: using System; using System.Text.RegularExpressions; class Test { static void Main() { string[] state1 = {On Off On Off On Off}; string[] state2 = {On On On Off On Off}; Console.WriteLine(Validate(state1)); // True Console.WriteLine(Validate(state2)); // False Console.ReadKey(); } static bool Validate(string[] state) { string text = String.Join( state); string regExp = ^(OnOff)+$; return Regex.IsMatch(text regExp); } } It can of course be easily turned into a one-liner if that's what's needed: bool isValid = Regex.IsMatch ( String.Join( state) ^(OnOff)+$);

Vulpes · Answer

Try this revised version: using System; using System.Linq; using System.Text.RegularExpressions; class Test { static void Main() { string[] ArrayElement = new string[6]; ArrayElement[0]= 1:05:00 PM 06/25/2013 On; ArrayElement[1]= 1:10:00 PM 06/25/2013 Off; ArrayElement[2]= 1:15:00 PM 06/25/2013 On; ArrayElement[3]= 1:20:00 PM 06/25/2013 Off; ArrayElement[4]= 1:25:00 PM 06/25/2013 On; ArrayElement[5]= 1:30:00 PM 06/25/2013 Off; Console.WriteLine(Validate(ArrayElement)); // True ArrayElement[2]= 1:15:00 PM 05/25/2013 On; Console.WriteLine(Validate(ArrayElement)); // False Console.ReadKey(); } static bool Validate(string[] state) { string f = h:mm:ss tt MM/dd/yyyy; // extract time stamps and make sure they're in sequence DateTime[] stamps = state .Select(s => DateTime.ParseExact(s.Substring(0 s.LastIndexOf( )) f null)).ToArray(); for(int i = 1; i { if(stamps[i] } // extract On/Off's and validate them state = state.Select(s => s.Substring(s.IndexOf(O))).ToArray(); string text = String.Join( state); string regExp = ^(OnOff)+$; return Regex.IsMatch(text regExp); } }

David Smith · Answer

Add a few more things to the logic. Vuples I left something out. The State Array will also contain a tStamp and State concatenated together. The format will like this below. ArrayElement[0]= 1:05:00 PM 06/25/2013 On ArrayElement[1]= 1:10:00 PM 06/25/2013 Off ArrayElement[2]= 1:15:00 PM 06/25/2013 On ArrayElement[3]= 1:20:00 PM 06/25/2013 Off ArrayElement[4]= 1:25:00 PM 06/25/2013 On ArrayElement[5]= 1:30:00 PM 06/25/2013 Off So how to modify regex and logic to account for the entire string logic base upon the array above static bool Validate(string[] state) { string text = String.Join( state); string regExp = ^(OnOff)+$; return Regex.IsMatch(text regExp); } Lastly Since the goal is to really add up the time an object has been off I need to add in some logic to do something if a cycle or element gets corrupt. A complete cycle is On/Off. At the moment your function is only validating whether is the Array has a complete On/Off Cycle. Let me give an example of an invalid array. The array is been initialized from an input file. Invalid Array Example: ArrayElement[2] data can't be calculated because the timestamp is not in range if that make sense. So if a case like that were to happen I want to do something so I am trying to come up with a linq that will account for a perfect sequence and Perfect timestamp sequence. ArrayElement[0]= 1:05:00 PM 06/25/2013 On ArrayElement[1]= 1:10:00 PM 06/25/2013 Off ArrayElement[2]= 1:15:00 PM 05/25/2013 On ArrayElement[3]= 1:20:00 PM 06/25/2013 Off ArrayElement[4]= 1:25:00 PM 06/25/2013 On ArrayElement[5]= 1:30:00 PM 06/25/2013 Off

Hemant Srivastava · Answer

Is there any condition on starting state.. I mean starting state must be 'ON' or it could be 'OFF'.