DelphiBasics Pointer Type Defines a general use Pointer to any memory based data System unit

type Pointer;

Description The Pointer type provides a general use pointer to any memory based variable. That is, one that is accessed by reference.   Objects, AnsiStrings, and arrays are examples of reference based variables.   But be warned : untyped pointers are dangerous - it is normally always better to use a specific pointer reference to the data type you are using. Only then can you act up on the pointer, as in the example. Related commands PAnsiChar A pointer to an AnsiChar value PAnsiString Pointer to an AnsiString value PChar A pointer to an Char value PCurrency Pointer to a Currency value PDateTime Pointer to a TDateTime value PExtended Pointer to a Extended floating point value PInt64 Pointer to an Int64 value PShortString A pointer to an ShortString value PString Pointer to a String value PVariant Pointer to a Variant value PWideChar Pointer to a WideChar PWideString Pointer to a WideString value  Download this web site as a Windows program.

Example code : Referring to the current form using a Pointer variable var   generalPtr : Pointer;  // A pointer to anything   formPtr    : ^TForm;  // A pointer to a form object begin   // The current unit's form is addressable via the self keyword   generalPtr := Addr(self);   // We can assign this pointer to the form pointer   formPtr := generalPtr;   // And set the form caption to show this   formPtr.Caption := 'Test program'; end; Show full unit code   The form is shown with caption:      Test program

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