API Reference > bentleyjs-core > Ids > Id64 > Id64.fromJSON Id64.fromJSON Function Create an Id64String from its JSON representation. fromJSON(prop?: string): Id64String note if the input is undefined, the result is "0", indicating an invalid Id. note if the input is not undefined, the result is the same as that of Id64.fromString. Parameter Type Description prop string The JSON representation of an Id. Returns - Id64String A well-formed Id string. Defined in core/bentley/src/Id.ts Line 101 Last Updated: 11 June, 2024