Session: Querying: How to use highlighting?

Highlighting can be a great feature for increasing search UX. To take leverage of it use Highlight method which is a part of query customizations available from Customize.

Syntax

// Make a full-text search dynamic query:
// ======================================
List<Employee> employeesResults = session
   // Make a dynamic query on 'Employees' collection
  .Query<Employee>()
   // Search for documents containing the term 'sales' in their 'Notes' field
  .Search(x => x.Notes, "sales")
   // Request to highlight the searched term by calling 'Highlight'
  .Highlight(
      x => x.Notes, // The document-field name in which we search
      35,           // Max length of each text fragment
      4,            // Max number of fragments to return per document
      out Highlightings salesHighlights) // An out param for getting the highlighted text fragments
   // Execute the query
  .ToList();

Parameters
fieldName	string	Name of a field to highlight.
fragmentLength	int	Maximum length of text fragments that will be returned.
fragmentCount	int	Maximum number of fragments that will be returned.
fragmentsField	string	Field in returned results containing highlight fragments (mutually exclusive with 'highlightings').
highlightings	FieldHighlightings	Instance of a FieldHighlightings that contains the highlight fragments for each returned result (mutually exclusive with 'fragmentsField').

Return Value
IDocumentQueryCustomization	Returns self for easier method chaining.
FieldHighlightings	Instance of a FieldHighlightings that contains the highlight fragments for each returned result (mutually exclusive with 'fragmentsField').

Example

// Make a full-text search dynamic query:
// ======================================
List<Employee> employeesResults = await asyncSession
   // Make a dynamic query on 'Employees' collection
  .Query<Employee>()
   // Search for documents containing the term 'sales' in their 'Notes' field
  .Search(x => x.Notes, "sales")
   // Request to highlight the searched term by calling 'Highlight'
  .Highlight(
      x => x.Notes, // The document-field name in which we search
      35,           // Max length of each text fragment
      4,            // Max number of fragments to return per document
      out Highlightings salesHighlights) // An out param for getting the highlighted text fragments
   // Execute the query
  .ToListAsync();