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property BeforeGetParams: TRemoteEvent read FBeforeGetParams write FBeforeGetParams;


__property Datasnap::Dbclient::TRemoteEvent BeforeGetParams = {read=FBeforeGetParams, write=FBeforeGetParams};


Type Visibility Source Unit Parent
event protected
Datasnap.Provider TCustomProvider


Occurs before the provider creates an OleVariant that encodes the current parameter values and sends them to a client dataset.

Write a BeforeGetParams event handler to respond to custom information from a client dataset. BeforeGetParams is part of the mechanism by which a provider and a client dataset communicate information during parameter fetching. When the provider is part of a stateless application server, this mechanism allows the provider and the client dataset to communicate persistent state information.

When the client dataset fetches parameter values from the provider, the following events occur:

1.The client dataset receives a BeforeGetParams event, where it can encode custom information into an OleVariant.

2.The provider receives a BeforeGetParams event, where the OleVariant from the client dataset appears as the OwnerData parameter. The provider can respond to or change that information before it fetches and encodes the parameter values.

3.The provider generates an OleVariant for the current parameter values of its dataset, if appropriate.

4.The provider receives an AfterGetParams event, where it can encode custom information into its OwnerData parameter or respond to information from the BeforeGetParams event handler.

5.The client dataset receives an AfterGetParams event, where it can respond to the custom information returned by the provider in its AfterGetParams event handler.

BeforeGetParams is of type Datasnap.DBClient.TRemoteEvent.

See Also