API Reference > presentation-common > Core Core Common types used all across Presentation packages. Classes Name Description KeySet A class that holds multiple KeySet.Key objects. PresentationError An error type thrown by Presentation APIs. RegisteredRuleset A ruleset that is registered in a ruleset manager. RulesetsFactory A factory class that can be used to create presentation rulesets targeted towards Constants Name Description DEFAULT_KEYS_BATCH_SIZE Default (recommended) keyset batch size for cases when it needs to be sent Enumerations Name Description PresentationStatus Status codes used by Presentation APIs. VariableValueTypes Possible variable value types Global Functions Name Description getInstancesCount Get total number of instances included in the supplied key set. isSingleElementPropertiesRequestOptions Checks if supplied request options are for single or multiple element properties. Beta Interfaces Name Description BooleanRulesetVariable Data structure for representing boolean ruleset variables. BooleanRulesetVariableJSON JSON representation of BooleanRulesetVariable. ClassInfo Information about an ECClass ClassInfoJSON A serialized version of ClassInfo CompressedClassInfoJSON A serialized and compressed version of ClassInfo ContentDescriptorRequestOptions Request type for content descriptor requests. ContentInstanceKeysRequestOptions Request type for content instance keys' requests. Beta ContentRequestOptions Request type for content requests. ContentSourcesRequestOptions Request type for content sources requests. Beta DisplayLabelRequestOptions Request type for label requests DisplayLabelsRequestOptions Request type for labels requests DistinctValuesRequestOptions Request type for distinct values' requests. EnumerationChoice A single choice in enumeration EnumerationInfo Enumeration information FilterByInstancePathsHierarchyRequestOptions Request type of filtering hierarchies by given ECInstance paths. FilterByTextHierarchyRequestOptions Request type of filtering hierarchies by given text. HierarchyCompareInfo Information about hierarchy modification / differences. HierarchyCompareInfoJSON JSON representation of HierarchyCompareInfo. HierarchyCompareOptions Data structure for comparing a hierarchy after ruleset or ruleset variable changes. HierarchyRequestOptions Request type for hierarchy requests. Id64RulesetVariable Data structure for representing ID ruleset variables. Id64RulesetVariableJSON JSON representation of Id64RulesetVariable. Id64sRulesetVariable Data structure for representing ID array ruleset variables. Id64sRulesetVariableJSON JSON representation of Id64sRulesetVariable. InstanceKey A key that uniquely identifies an instance in an iModel InstanceKeyJSON A serialized version of InstanceKey IntRulesetVariable Data structure for representing int ruleset variables. IntRulesetVariableJSON JSON representation of IntRulesetVariable. IntsRulesetVariable Data structure for representing int array ruleset variables. IntsRulesetVariableJSON JSON representation of IntsRulesetVariable. KeySetJSON A data structure of serialized KeySet KindOfQuantityInfo Kind of quantity information MultiElementPropertiesRequestOptions Request type for multiple elements properties requests. Beta NodeDeletionInfo Information about node deletion. NodeDeletionInfoJSON JSON representation of NodeDeletionInfo. NodeInsertionInfo Information about node insertion. NodeInsertionInfoJSON JSON representation of NodeInsertionInfo. NodeUpdateInfo Information about node update. NodeUpdateInfoJSON JSON representation of NodeUpdateInfo. PagedResponse A structure for paged responses PageOptions Paging options PropertyInfo A structure that describes an ECProperty PropertyInfoJSON A serialized version of PropertyInfo RelatedClassInfo A structure that describes a related class and the properties of that relationship. RelatedClassInfoJSON A serialized version of RelatedClassInfo RequestOptions A generic request options type used for both hierarchy and content requests. RequestOptionsWithRuleset Options for requests that require presentation ruleset. RulesetVariableBase Base data structure for representing ruleset variables. RulesetVariableBaseJSON JSON representation of RulesetVariableBase. SelectionScopeRequestOptions Request options used for selection scope related requests SingleElementPropertiesRequestOptions Request type for single element properties requests. Beta StringRulesetVariable Data structure for representing string ruleset variables. StringRulesetVariableJSON JSON representation of StringRulesetVariable. StrippedRelatedClassInfo Data structure that contains a subset of RelatedClassInfo required to ValuesDictionary A dictionary data structure. Namespaces Name Description ClassInfo HierarchyCompareInfo InstanceKey Key PartialHierarchyModification PropertyInfo RelatedClassInfo RelatedClassInfoWithOptionalRelationship RelationshipPath RulesetVariable Type Aliases Name Description ClassId Type of an ECClass ID. ComputeDisplayValueCallback ElementPropertiesRequestOptions Request type for element properties requests Beta InstanceId Type of an ECInstance ID. Key A single key that identifies something in an iTwin.js application Keys A type for multiple keys that identify something in iModel.js application Omit Create a type with T properties excluding properties listed in K. Paged A wrapper type that injects PageOptions into supplied type PartialBy Create a type from given type T and make specified properties optional. PartialHierarchyModification Information about a hierarchy change: insertion, deletion or node update. PartialHierarchyModificationJSON JSON representation of PartialHierarchyModificationJSON.PartialHierarchyModification. PrimitivePropertyValue Value of a primitive property. Prioritized A wrapper type that injects priority into supplied type. RelatedClassInfoWithOptionalRelationship A structure that describes a relationship between source and target classes where RelatedClassInfoWithOptionalRelationshipJSON RelationshipPath A structure that describes a related class path. RelationshipPathJSON Serialized RelationshipPathJSON.RelationshipPath RulesetVariable Data structure for representing ruleset variables. RulesetVariableJSON JSON representation of RulesetVariableJSON.RulesetVariable. StrippedRelationshipPath Data structure that contains a subset of StrippedRelationshipPath.RelationshipPath required to Subtract Create a type with T properties excluding all properties in type K. VariableValue Union of all supported variable value types VariableValueJSON JSON representation of VariableValue Last Updated: 06 January, 2022