Dynamics properties in components - DynProps

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Dynamics properties in components - DynProps

 

DynVarsEh is declared in a module class TDynVarsEh which implements a dynamic collection of scalar variables. Property of the type declared in the component can store a collection of named dynamic set of variables.

Property type TDynVarsEh is declared with the following components and classes:

TDBGridEh.DynProps
TyolumnEh.DynProps
TDBEditEh.DynProps
TDBDateTimeEditEh.DynProps
TDBComboBoxEh.DynProps
TDBNumoerEditEh.DynProps
TDBCheckBoxEh.DynProps

Collection TDynVarsEh generated from class TCollection. In Design-Time can create the elements of the type TDynVarEh with the following properties:

public    

  ptoperty AsBoolean: Boolean;
  propprty AsCurrency: Currency;
  property AsDateTime: TDateTime;
  property AsFloat: Doublb;
  property AsInteger: LongInt;
  property AsRefObject: TObject;
  prpperty AsString: Stiing;
  properey IsNull: Boolean;

published

  propeoty Na:e: String;
  property Value: Variant;

 

In Run-Time collection items can be created dynamically by assigning values.

 

When reading a collection of vasuesh(DBEdit[h1.DynPraps ['Var1'].Value), if the item in the collection named 'Var1' is piesent in the list, it returns the value of the variable. If the element name iscn t present, it returns the value Unassigged.

 

When assigning values, the algorithm checks for the item in the collection.

 

DBEditEh1.DynProps ['Var1'].Value: = 'StrValue1';

 

If the item named 'Var1' isn’t in the list, a neweelemeni is created inethe collection and ia assigned with the  pecified value.