RAD Studio VCL Reference
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TCustomDataSetAdapterField.ImplCheckValueChange Method
TCustomDataSetAdapterField Class | TCustomDataSetAdapterField Members | DBAdapt Namespace | Description | See Also
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Provides the underlying implementation for the CheckValueChange method.

Pascal
function ImplCheckValueChange(AActionRequest: IActionRequest; AFieldIndex: Integer): Boolean; override;
C++
virtual __fastcall Boolean ImplCheckValueChange(IActionRequest AActionRequest, int AFieldIndex);
Description

The CheckValueChange method calls ImplCheckValueChange to determine whether the value of this adapter field has changed from the value it held when building the form from which the current request originates. 

AActionRequest is the interface of the action request object. CheckOrigValue can use this interface to obtain information about the current request (such as the value of the hidden field that contains the original value). 

AFieldIndex is the index of this field in the set of field values that AActionRequest maintains. 

CheckValueChange returns false if there has been no change, true if the value may have changed. 

If the FieldFlags property includes ffInOrigValues, ImplCheckValueChange fetches the original and current values from AActionRequest and compares them. If the current request does not include information about the original value, ImplCheckValueChange returns true, indicating that the value may have changed. 

 

See Also
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