internal static void Encode(HL7Separators seps, System.Text.StringBuilder sb, Type type, object value)
{
if (value == null)
{
// Do nothing
}
else if (type.IsArray)
{
foreach (object element in value as Array)
{
Encode(seps, sb, type.GetElementType(), element);
sb.Append(seps.FieldRepeatSeparator);
}
// Remove the last field repeat separator.
sb.Remove(sb.Length - 1, 1);
}
else if (type.Equals(typeof(string)))
{
sb.Append(seps.Encode(value as string));
}
else
{
foreach (FieldInfo component in type.GetFields())
{
HL7Component.Encode(seps, sb, component.FieldType, component.GetValue(value));
sb.Append(seps.ComponentSeparator);
}
// Remove the last component separator.
sb.Remove(sb.Length - 1, 1);
}
}
internal void Encode(HL7Separators seps, System.Text.StringBuilder sb)
{
FieldInfo[] fields = GetType().GetFields();
sb.Append(GetType().Name);
sb.Append(seps.FieldSeparator);
foreach (FieldInfo field in fields)
{
if (this is MSH && field.Name.Equals("FieldSeparator"))
{
// A field separator was already added after the segment HL7Name, don't add another.
}
else if (this is MSH && field.Name.Equals("EncodingCharacters"))
{
// We want the encoding characters raw, not escaped.
sb.Append(field.GetValue(this));
sb.Append(seps.FieldSeparator);
}
else
{
HL7Field.Encode(seps, sb, field.FieldType, field.GetValue(this));
sb.Append(seps.FieldSeparator);
}
}
}
/// <summary>
/// Encode message according to HL7 encoding rules with specified separators.
/// </summary>
/// <param HL7Name="seps">Characters to separate segments, fields, field repeats, components and subcomponents</param>
/// <returns>Bytes for HL7 message</returns>
public string Encode(HL7Separators seps)
{
StringBuilder sb = new StringBuilder();
// Encode this full message as a segment group
base.Encode(seps, sb);
return(Cleanup(seps, sb.ToString()));
}
/// <summary>
/// Parses the received HL7 message.
/// </summary>
/// <param name="messageForm">The raw message encoded in HL7 'pipes and hats' format.</param>
/// <returns>The parsed HL7 message object</returns>
/// <exception cref="HL7ParseException">Thrown when parsing fails</exception>
public static HL7Message Parse(string messageForm)
{
// Determine the HL7 separators dynamically from the incoming message (usually "|^~\&")
HL7Separators sep = new HL7Separators(messageForm);
// Change CRLF or LF into the standard CR separators
if (messageForm.Contains("\r\n"))
{
messageForm = messageForm.Replace("\r\n", "\r");
}
if (messageForm.Contains("\n"))
{
messageForm = messageForm.Replace("\n", "\r");
}
// Remove consecutive segment separators
while (messageForm.Contains("\r\r"))
{
messageForm = messageForm.Replace("\r\r", "\r");
}
// Parse all the segments
messageForm = messageForm.TrimEnd(new char[] { sep.SegmentSeparator });
string[] segmentForm = messageForm.Split(sep.SegmentSeparator);
for (int count = 0; count < segmentForm.Count(); count++)
{
segmentForm[count] = segmentForm[count].Replace("\n", string.Empty);
}
HL7Segment[] segments = new HL7Segment[segmentForm.Length];
for (int i = 0; i < segmentForm.Length; i++)
{
segments[i] = HL7Segment.Parse(segmentForm[i], sep);
}
// Grab the MSH segment in order to determine which message structure to use
MSH msh = segments[0] as MSH;
if (msh == null)
{
throw new HL7ParseException(ConstantsResource.HL7NoMshSegment);
}
if (msh.MessageType == null)
{
throw new HL7ParseException(ConstantsResource.NoMessageType);
}
// Determine the structure for the indicated message identifier
Type messageStructure = GetMessageStructure(msh.MessageType);
// Create the message and populate all the matching segments into its structure
int segmentIndex = 0;
HL7Message message = BuildSegmentGroup(messageStructure, segments, ref segmentIndex) as HL7Message;
return(message);
}
/// <summary>
/// Encode segment group according to HL7 encoding rules with specified separators.
/// </summary>
/// <param HL7Name="seps">Characters to separate segments, fields, field repeats, components and subcomponents</param>
/// <param HL7Name="sb">String builder</param>
public void Encode(HL7Separators seps, StringBuilder sb)
{
var segmentGroupFields = GetType().GetFields().OrderBy(f => f.MetadataToken);
foreach (FieldInfo segmentGroupField in segmentGroupFields)
{
if (segmentGroupField.FieldType.IsArray)
{
Array array = segmentGroupField.GetValue(this) as Array;
foreach (object segmentGroupObject in array)
{
// Each item in the array could be another group of segments or a single segment
if (segmentGroupObject is HL7SegmentGroup)
{
HL7SegmentGroup segmentGroup = segmentGroupObject as HL7SegmentGroup;
segmentGroup.Encode(seps, sb);
}
else
{
HL7Segment segment = segmentGroupObject as HL7Segment;
segment.Encode(seps, sb);
sb.Append(seps.SegmentSeparator);
}
}
}
else
{
// The non-repeating item could be a another group of segments, or a single segment, or null
object segmentGroupObject = segmentGroupField.GetValue(this);
if (segmentGroupObject is HL7SegmentGroup)
{
HL7SegmentGroup segmentGroup = segmentGroupObject as HL7SegmentGroup;
segmentGroup.Encode(seps, sb);
}
else if (segmentGroupObject != null)
{
HL7Segment segment = segmentGroupObject as HL7Segment;
segment.Encode(seps, sb);
sb.Append(seps.SegmentSeparator);
}
}
}
}
public static object Parse(Type type, string componentForm, HL7Separators sep)
{
object component;
// A component can either be a string, or it will consist of sub-components.
if (type.Equals(typeof(string)))
{
component = sep.Decode(componentForm);
}
else
{
FieldInfo[] subcomponents = type.GetFields();
string[] subcomponentForm = componentForm.Split(sep.SubcomponentSeparator);
int n = Math.Min(subcomponents.Length, subcomponentForm.Length);
// Invoke the constructor that takes no parameters
component = type.GetConstructor(System.Type.EmptyTypes).Invoke(null);
for (int i = 0; i < n; i++)
{
// Each subcomponent must be a string
if (subcomponents[i].FieldType.Equals(typeof(string)))
{
subcomponents[i].SetValue(component, sep.Decode(subcomponentForm[i]));
}
else if (subcomponents[i].FieldType.Equals(typeof(HL7.Common.DataStructure.HD))) // For OBR segment PrincipalResultsInterpreter field we have assigningAuthority that needs to be set
{
object objHD = new HL7.Common.DataStructure.HD();
FieldInfo[] subcomponentsHD = objHD.GetType().GetFields();
for (int j = 0; j < subcomponentsHD.Length; j++)
{
if (subcomponentsHD[j].Name == "universalID") // Set the UniversalID
{
subcomponentsHD[j].SetValue(objHD, sep.Decode(subcomponentForm[i])); //
subcomponents[i].SetValue(component, objHD);
}
}
}
else
{
throw new HL7ParseException(string.Format(ConstantsResource.SubcomponentNotString, subcomponents[i].GetType()));
}
}
}
return(component);
}
public static object Parse(Type type, string fieldForm, HL7Separators sep)
{
object field;
// A field can be an array of repeats, or a string identifier, or a data structure with components
if (type.IsArray)
{
Type elementType = type.GetElementType();
string[] elementForm;
if (fieldForm.IndexOf(sep.FieldRepeatSeparator) == -1 && fieldForm.IndexOf(sep.ComponentSeparator) > -1 && elementType.Equals(typeof(string)))
{
elementForm = fieldForm.Split(sep.ComponentSeparator);
}
else
{
elementForm = fieldForm.Split(sep.FieldRepeatSeparator);
}
Array array = Array.CreateInstance(elementType, elementForm.Length);
for (int i = 0; i < elementForm.Length; i++)
{
array.SetValue(HL7Field.Parse(elementType, elementForm[i], sep), i);
}
field = array;
}
else if (type.Equals(typeof(string)))
{
field = sep.Decode(fieldForm);
}
else
{
FieldInfo[] components = type.GetFields();
string[] componentForm = fieldForm.Split(sep.ComponentSeparator);
int n = Math.Min(components.Length, componentForm.Length);
// Invoke the constructor that takes no parameters
field = type.GetConstructor(System.Type.EmptyTypes).Invoke(null);
for (int i = 0; i < n; i++)
{
object value = HL7Component.Parse(components[i].FieldType, componentForm[i], sep);
components[i].SetValue(field, value);
}
}
return(field);
}
public static HL7Segment Parse(string segmentForm, HL7Separators sep)
{
// Split the segment into fields and create the object for the indicated segment identifier
string[] fieldForm = segmentForm.Split(sep.FieldSeparator);
HL7Segment segment = CreateBlankSegment(fieldForm[0]);
if (segment == null)
{
return(new UnknownSegment()
{
FieldForm = fieldForm
});
}
// Parse each of the fields according to its declared identifier in the segment structure.
// Some fields will be repeating, some will be strings and some will have components.
PopulateSegment(sep, fieldForm, segment);
return(segment);
}
/// <summary>
/// Cleans up an HL7 message by removing redundant separators.
/// </summary>
/// <param name="seps">The defined separators for the message</param>
/// <param name="messageForm">The message to be cleaned up</param>
/// <returns>The cleaned message</returns>
private static string Cleanup(HL7Separators seps, string messageForm)
{
// Save the first 8 characters which contain the HL7 encoding characters that should not be normalised.
const int PREAMBLE_LENGTH = 8;
string preamble = messageForm.Substring(0, PREAMBLE_LENGTH);
messageForm = messageForm.Substring(PREAMBLE_LENGTH);
// e.g. input: a&^&~&^&|&^&~&^&\r
// step 1: a^&~^&|^&~^&\r (removed & before ^)
// step 2: a^~^&|^~^&\r (removed & before ~)
// step 3: a^~^|^~^&\r (removed & before |)
// step 4: a^~^|^~^\r (removed & before \r)
// step 5: a~^|~^\r (removed ^ before ~)
// step 6: a~|~^\r (removed ^ before |)
// step 7: a~|~\r (removed ^ before \r)
// step 8: a|~\r (removed ~ before |)
// step 9: a|\r (removed ~ before \r)
// step 10: a\r (removed | before \r)
RemoveRedundantSeparator(ref messageForm, seps.SubcomponentSeparator, seps.ComponentSeparator);
RemoveRedundantSeparator(ref messageForm, seps.SubcomponentSeparator, seps.FieldRepeatSeparator);
RemoveRedundantSeparator(ref messageForm, seps.SubcomponentSeparator, seps.FieldSeparator);
RemoveRedundantSeparator(ref messageForm, seps.SubcomponentSeparator, seps.SegmentSeparator);
RemoveRedundantSeparator(ref messageForm, seps.ComponentSeparator, seps.FieldRepeatSeparator);
RemoveRedundantSeparator(ref messageForm, seps.ComponentSeparator, seps.FieldSeparator);
RemoveRedundantSeparator(ref messageForm, seps.ComponentSeparator, seps.SegmentSeparator);
RemoveRedundantSeparator(ref messageForm, seps.FieldRepeatSeparator, seps.FieldSeparator);
RemoveRedundantSeparator(ref messageForm, seps.FieldRepeatSeparator, seps.SegmentSeparator);
RemoveRedundantSeparator(ref messageForm, seps.FieldSeparator, seps.SegmentSeparator);
return(preamble + messageForm);
}
/// <summary>
/// Parses each of the fields according to its declared identifier in the segment structure.
/// Ignores any extra fields either in the received segment or in the structure.
/// </summary>
/// <param HL7Name="sep">Separators to use for repeating fields, components and subcomponents</param>
/// <param HL7Name="fieldForm">Encoded segment split into fields, where fieldForm[0] is the segment name</param>
/// <param HL7Name="segment">Empty object of desired segment structure</param>
private static void PopulateSegment(HL7Separators sep, string[] fieldForm, HL7Segment segment)
{
FieldInfo[] fields = segment.GetType().GetFields();
// Subtract one from the number of fields in the received segment to avoid counting the segment name.
int offset = 1;
// Except when segment is MSH, then have no offset but the first field is the field separator.
if (fieldForm[0].Equals("MSH"))
{
fields[0].SetValue(segment, "" + sep.FieldSeparator);
offset = 0;
}
int n = Math.Min(fields.Length, fieldForm.Length - 1);
for (int i = 1 - offset; i < n; i++)
{
object value = HL7Field.Parse(fields[i].FieldType, fieldForm[i + offset], sep);
fields[i].SetValue(segment, value);
}
}
/// <summary>
/// Creates a negative HL7 acknowledgement for an unparseable message.
/// </summary>
/// <param HL7Name="errorMessage">A description of the error</param>
/// <returns>The HL7 acknowledgement</returns>
public static HL7Acknowledgement AcknowledgeUnparseableMessage(string errorMessage)
{
HL7Separators typical = new HL7Separators();
HL7Acknowledgement ack = new HL7Acknowledgement();
ack.MessageHeader = new MSH();
ack.MessageHeader.FieldSeparator = typical.FieldSeparator.ToString();
ack.MessageHeader.EncodingCharacters = typical.EncodingCharacters;
ack.MessageHeader.SendingApplication = new HD()
{
namespaceID = "HIPS"
};
ack.MessageHeader.SendingFacility = new HD()
{
namespaceID = "HIPS"
};
ack.MessageHeader.ReceivingApplication = new HD()
{
namespaceID = "HIPS"
};
ack.MessageHeader.ReceivingFacility = new HD()
{
namespaceID = "HIPS"
};
ack.MessageHeader.DateTimeOfMessage = new TS()
{
TimestampValue = DateTime.Now
};
ack.MessageHeader.MessageControlID = NewMessageControlID();
ack.MessageAcknowledgement = new MSA();
ack.MessageAcknowledgement.AcknowledgmentCode = "AE";
ack.MessageAcknowledgement.ErrorCondition = new CE()
{
text = errorMessage
};
return(ack);
}
internal static void Encode(HL7Separators seps, System.Text.StringBuilder sb, Type type, object value)
{
// A component is either empty, a string or an HL7 data structure containing subcomponents.
if (value == null)
{
// Do nothing
}
else if (value is string)
{
sb.Append(seps.Encode(value as string));
}
else
{
foreach (FieldInfo subcomponent in type.GetFields())
{
// A subcomponent is always a string
sb.Append(seps.Encode(subcomponent.GetValue(value) as string));
sb.Append(seps.SubcomponentSeparator);
}
// Remove the extraneous subcomponent separator
sb.Remove(sb.Length - 1, 1);
}
}
