The ISearchFields type exposes the following members.
Adds new field to collection. When field already exists, it will be updated (merged with existing one). When adding content field with it's value multiple times, the value is appended to existing content.
Returns requested field. Null when field doesn't exist.
Prepares value to add to content field.
Appends data to CONTENT field. Field is created if it's not already present.(Defined by SearchFieldsExtensions.)
Ensures CONTENT field in collection. Field is created if it's not already present.(Defined by SearchFieldsExtensions.)