It's just like any string:
public enumerateObjectInstances(options: EnumerateVisualObjectInstancesOptions): VisualObjectInstanceEnumeration { let objectName = options.objectName; let objectEnumeration: VisualObjectInstance[] = []; switch(objectName) { case 'kpi': objectEnumeration.push({ objectName: objectName, properties: { displayUnits: this.kpiSettings.kpi.displayUnits }, selector: null }); break; }; return objectEnumeration; }