core.hl7segment | Medplum

Hl7Segment class

The Hl7Segment class represents one HL7 segment. A segment is a collection of fields. The name field is the first field.

Signature:

export declare class Hl7Segment

Constructors

Constructor Modifiers Description
(constructor)(fields, context) Creates a new HL7 segment.
Field strings are not parsed until they are accessed via Hl7Segment.getField() or via the Hl7Segment.fields getter.

Properties

Property Modifiers Type Description
context readonly Hl7Context
fields readonly Hl7Field Returns all HL7 fields, parsing any unparsed field strings on first access.
Prefer Hl7Segment.getField() when you only need a subset of fields; that method avoids parsing unrelated fields.
name readonly string

Methods

Method Modifiers Description
get(index) Returns an HL7 field by index.
getComponent(fieldIndex, component, subcomponent, repetition) Returns an HL7 component by field index and component index.
This is a shortcut for getField(field).getComponent(component).
Note that both indices are 1-based, not 0-based.
For example, to get the first component, use getComponent(1, 1).
This aligns with HL7 component names such as MSH.9.2.
getField(index) Returns an HL7 field by index.
Note that the index is 1-based, not 0-based.
For example, to get the first field, use getField(1).
This aligns with HL7 field names such as PID.1, PID.2, etc.
Field zero is the segment name.
Fields are lazily parsed; the requested field is parsed and cached on demand.
parse(text, context) static Parses an HL7 segment string into an Hl7Segment object.
setComponent(fieldIndex, component, value, subcomponent, repetition) Sets a component value by field index and component index. This is a shortcut for getField(field).setComponent(component, value). Note that both indices are 1-based, not 0-based.
setField(index, field) Sets a field at the specified index. If that index does not exist, it will be added. Note that the index is 1-based, not 0-based.
toString() Returns the HL7 segment as a string.
Unparsed fields are emitted directly from their original string form, which preserves the source text without forcing a parse.