API Reference > bentleyjs-core > Ids > Id64 > Id64.fromLocalAndBriefcaseIds Id64.fromLocalAndBriefcaseIds Function Produce an Id string from a local and briefcase Id. fromLocalAndBriefcaseIds(localId: number, briefcaseId: number): Id64String Parameter Type Description localId number The non-zero local Id as an unsigned 40-bit integer. briefcaseId number The briefcase Id as an unsigned 24-bit integer. Returns - Id64String an Id64String containing the hexadecimal string representation of the unsigned 64-bit integer which would result from the operation localId | (briefcaseId << 40), or an invalid Id "0" if the inputs are invalid. Defined in core/bentley/src/Id.ts Line 160 Last Updated: 13 June, 2024