HL7 Parsing using .NET

Free HL7 Parser:
The HL7(Health Level 7) message is very familior to the people who are working on HealthCare Projects.It is like a plain txt file with some seperator and contain verious kind of message like patient details,Admit/Visit Notification,Pharmacy Details etc.But there can be multi level seperator.The message structure are very complex,So its not so easy to parse the message programatically.
HL7 message can be parsed easily from .NET by the help of nHAPI.This are free dll.

Download nHapi

How to use...
If you like to parse the HL7 files programatically,you first want to know the Message structure of that particular message type of HL7.HL7 message have different version (like 2.1,2.5,2.5.1,2.6 etc) and each version have different message type like(ADT_A01,ADT_A02,ADT_A03).ADT_A01 message describes Admit/Visit Notification,ADT_A01 describes Transfer a patient etc.To describes the details of each message type is out of the scope.
Now using nHAPI you can extract the fields of a HL7 message.
I am writing some code which will extract some fields like PID,FamilySurname,GivenName,MiddleInitial,DOB,Sex .I have taken some V 2.5 message for this example.

Message type:ADT_A01

Message:MSH^~\&7EDIT7EDIT.COM20090211120829ADT^A01P2.5EVNA01198808181123PIDPATID1234^5^M11JONES^WILLIAM^A^III19610615MC1200 N ELM STREET^^GREENSBORO^NC^27401-1020GL(919)379-1212(919)271-3434~(919)277-3114SPATID12345001^2^M101234567899-87654^NCNK11JONES^BARBARA^KWIFE20011105NK11JONES^MICHAEL^AFATHERPV11I2000^2012^01004777^LEBAUER^SIDNEY^J.SUR-7A0AL11^PENICILLINPRODUCES HIVES~RASHAL12^CAT DANDERDG1001I91550MAL NEO LIVER, PRIMARY19880501103005FPR12234M11111^CODE151COMMON PROCEDURES198809081123ROL45^CANAB^ROLE MASTER LISTADROLKATE^SMITH^ELLEN199505011201GT111221519BILL^GATES^AIN1001A3571234BCMD132987IN2ID1551001SSN12345678ROL45^CANNS^ROLE MASTER LISTADROLKATE^ELLEN199505011201

CODING:
Step 1.Take a reference of two following dlls from the .NET
NHapi.Model.V25,NHapi.Base
Step 2.From the cs page import the namespace

using NHapi.Base;
using NHapi.Base.Parser;
using NHapi.Base.Model;
using NHapi.Model.V25;
using NHapi.Model.V25.Message;
using NHapi.Model.V25.Segment;

Step 3.Create an object of PipeParser as the class level

PipeParser parser = new PipeParser();

Step 4.Write a method which will parse the HL7
public void getADT_A01()
{
IMessage m = parser.Parse(strMessage);//str message will contain your HL7 Message
ADT_A01 adtA01 = m as ADT_A01;

string strPID = adtA01.PID.GetPatientIdentifierList(0).IDNumber.ToString(); string strFamilySurName = adtA01.PID.GetPatientName(0).FamilyName.Surname.

ToString();

string strGivenName = adtA01.PID.GetPatientName(0).GivenName.ToString();

string strMiddleInitial = adtA01.PID.GetPatientName(0).SecondAndFurtherGivenNamesOrInitialsThereof.ToString();

string strDOB = adtA01.PID.DateTimeOfBirth.Time.ToString();

string strSex = adtA01.PID.AdministrativeSex.ToString();

}

Now strFamilySurName,strGivenName ,strMiddleInitial ,strDOB ,strSex contain the FamilySurName,GivenName ,MiddleInitial ,DOB ,Sex respectively

Now take another example of ADT_A02 message
Message version-V2.5
Message:
MSH^~\&7EDIT7EDIT.COM20090211151404ADT^A02P2.5ALNEEVNA02200007250712PID1191959Franz^Lotte^MarieSchulz19560129F171 ZOBERLEIN^^ISHPEMING^ ^49849(900)485-5344(900)485-5344371-66-9256New York^American20010131PV1130148^ADDISON^JAMES123434

Method:
public void getADT_A02()
{
IMessage m = parser.Parse(hl7BO.HL7Message);
ADT_A02 adtA02 = m as ADT_A02;
string strPID = adtA02.PID.GetPatientIdentifierList(0).IDNumber.ToString(); string strFamilySurName = adtA02.PID.GetPatientName(0).FamilyName.Surname.ToString(); string strGivenName= adtA02.PID.GetPatientName(0).GivenName.ToString(); string strMiddleInitial = adtA02.PID.GetPatientName(0).SecondAndFurtherGivenNamesOrInitialsThereof.ToString();
string strDOB = adtA02.PID.DateTimeOfBirth.Time.ToString();
string strSex= adtA02.PID.AdministrativeSex.ToString();
}

In this way You can parse each & every message of HL7

Now do the parsing of other type of HL7 message by yourself.All the best.
Please feel free if you have any problem.