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CriteriaOperator.RegisterCustomAggregate(ICustomAggregate) Method

Registers a custom aggregate function to use in any CriteriaOperator-based criteria in your application.

Namespace: DevExpress.Data.Filtering

Assembly: DevExpress.Data.v23.1.dll

NuGet Package: DevExpress.Data


public static void RegisterCustomAggregate(
    ICustomAggregate customAggregate


Name Type Description
customAggregate ICustomAggregate

A custom aggregate function to register.


To access custom aggregate functions registered via the RegisterCustomAggregate and CriteriaOperator.RegisterCustomAggregates method calls, call the CriteriaOperator.GetCustomAggregates function. To search for a specific registered custom function, call the CriteriaOperator.GetCustomAggregate function.


  • The RegisterCustomAggregate method throws an exception if the customAggregate has already been registered.
  • The customAggregate must have a unique Name property value. If you use standard aggregate names (Min, Max, Sum, Avg, Single, Exists, and Count), an exception is raised.

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