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CPropExchange::ExchangeProp

Exchanges a property between a storage medium and the control.

virtual BOOL ExchangeProp( 
   LPCTSTR pszPropName, 
   VARTYPE vtProp, 
   void* pvProp, 
   const void* pvDefault = NULL  
) = 0;

Parameters

  • pszPropName
    The name of the property being exchanged.

  • vtProp
    A symbol specifying the type of the property being exchanged. Possible values are:

    Symbol

    Property Type

    VT_I2

    short

    VT_I4

    long

    VT_BOOL

    BOOL

    VT_BSTR

    CString

    VT_CY

    CY

    VT_R4

    float

    VT_R8

    double

  • pvProp
    A pointer to the property's value.

  • pvDefault
    Pointer to a default value for the property.

Return Value

Nonzero if the exchange was successful; 0 if unsuccessful.

Remarks

If the property is being loaded from the medium to the control, the property's value is retrieved from the medium and stored in the object pointed to by pvProp. If the property is being stored to the medium, the value of the object pointed to by pvProp is written to the medium.

The functions CArchivePropExchange::ExchangeProp, CResetPropExchange::ExchangeProp, and CPropsetPropExchange::ExchangeProp override this pure virtual function.

Requirements

Header: afxctl.h

See Also

Reference

CPropExchange Class

Hierarchy Chart

COleControl::DoPropExchange

CPropExchange::ExchangeBlobProp

CPropExchange::ExchangeFontProp

CPropExchange::ExchangePersistentProp