/// <summary>
/// Formats a <see cref="IMessage"/> object into an HL7 message string using the given encoding.
/// </summary>
/// <param name="source">An <see cref="IMessage"/> object from which to construct an encoded message string.</param>
/// <param name="encodingChars">Encoding characters to be used.</param>
/// <returns>The encoded message.</returns>
/// <exception cref="HL7Exception">Thrown if the data fields in the message do not permit encoding (e.g. required fields are null).</exception>
/// <exception cref="EncodingNotSupportedException">Thrown if the requested encoding is not supported by this parser.</exception>
public static string Encode(ISegment source, EncodingCharacters encodingChars)
{
var result = new StringBuilder();
result.Append(source.GetStructureName());
result.Append(encodingChars.FieldSeparator);
// start at field 2 for MSH segment because field 1 is the field delimiter
var startAt = 1;
if (IsDelimDefSegment(source.GetStructureName()))
{
startAt = 2;
}
// loop through fields; for every field delimit any repetitions and add field delimiter after ...
var numFields = source.NumFields();
for (var i = startAt; i <= numFields; i++)
{
try
{
var reps = source.GetField(i);
for (var j = 0; j < reps.Length; j++)
{
var fieldText = Encode(reps[j], encodingChars);
// if this is MSH-2, then it shouldn't be escaped, so un-escape it again
if (IsDelimDefSegment(source.GetStructureName()) && i == 2)
{
fieldText = Escape.UnescapeText(fieldText, encodingChars);
}
result.Append(fieldText);
if (j < reps.Length - 1)
{
result.Append(encodingChars.RepetitionSeparator);
}
}
}
catch (HL7Exception e)
{
Log.Error("Error while encoding segment: ", e);
}
result.Append(encodingChars.FieldSeparator);
}
// strip trailing delimiters ...
return(StripExtraDelimiters(result.ToString(), encodingChars.FieldSeparator));
}
/// <summary> Fills a field with values from an unparsed string representing the field. </summary>
/// <param name="destinationField">the field Type.
/// </param>
/// <param name="data">the field string (including all components and subcomponents; not including field delimiters).
/// </param>
/// <param name="encodingCharacters">the encoding characters used in the message.
/// </param>
private static void Parse(IType destinationField, string data, EncodingCharacters encodingCharacters)
{
var components = Split(data, Convert.ToString(encodingCharacters.ComponentSeparator));
for (var i = 0; i < components.Length; i++)
{
var subcomponents = Split(components[i], Convert.ToString(encodingCharacters.SubcomponentSeparator));
for (var j = 0; j < subcomponents.Length; j++)
{
var val = subcomponents[j];
if (val != null)
{
val = Escape.UnescapeText(val, encodingCharacters);
}
Terser.GetPrimitive(destinationField, i + 1, j + 1).Value = val;
}
}
}
