TStream

[Properties (by Name)][Methods (by Name)][Events (by Name)]

Base class for streams.

Declaration

Source position: classesh.inc line 937

Type
  TStream = class (TObject)
  protected
    procedure InvalidSeek;  Virtual;
    procedure Discard(const Count: Int64);
    procedure DiscardLarge(Count: Int64; const MaxBufferSize: LongInt);
    procedure FakeSeekForward(Offset: Int64; const Origin: TSeekOrigin; 
                             const Pos: Int64);
    function GetPosition : Int64;  Virtual;
    procedure SetPosition(const Pos: Int64);  Virtual;
    function GetSize : Int64;  Virtual;
    procedure SetSize64(const NewSize: Int64);  Virtual;
    procedure SetSize(NewSize: LongInt);  Virtual;  Overload;
    procedure SetSize(const NewSize: Int64);  Virtual;  Overload;
    procedure ReadNotImplemented;
    procedure WriteNotImplemented;
    function ReadMaxSizeData(var Buffer; aSize: NativeInt; 
                            aCount: NativeInt) : NativeInt;
    procedure ReadExactSizeData(var Buffer; aSize: NativeInt; 
                               aCount: NativeInt);
    function WriteMaxSizeData(const Buffer; aSize: NativeInt; 
                             aCount: NativeInt) : NativeInt;
    procedure WriteExactSizeData(const Buffer; aSize: NativeInt; 
                                aCount: NativeInt);
  public
    function Read(var Buffer; Count: LongInt) : LongInt;  Virtual;  Overload;
    function Read(var Buffer: TBytes; Count: LongInt) : LongInt;  Overload;
    function Read(Buffer: TBytes; aOffset: LongInt; Count: LongInt)
                  : LongInt;  Overload;
    function Write(const Buffer: TBytes; Offset: LongInt; Count: LongInt)
                   : LongInt;  Overload;
    function Write(const Buffer: TBytes; Count: LongInt) : LongInt
                  ;  Overload;
    function Write(const Buffer; Count: LongInt) : LongInt;  Virtual
                  ;  Overload;
    function Seek(Offset: LongInt; Origin: Word) : LongInt;  Virtual
                 ;  Overload;
    function Seek(const Offset: Int64; Origin: TSeekOrigin) : Int64
                 ;  Virtual;  Overload;
    function ReadData(Buffer: Pointer; Count: NativeInt) : NativeInt
                     ;  Overload;
    function ReadData(Buffer: TBytes; Count: NativeInt) : NativeInt
                     ;  Overload;
    function ReadData(var Buffer: Boolean) : NativeInt;  Overload;
    function ReadData(var Buffer: Boolean; Count: NativeInt) : NativeInt
                     ;  Overload;
    function ReadData(var Buffer: AnsiChar) : NativeInt;  Overload;
    function ReadData(var Buffer: AnsiChar; Count: NativeInt) : NativeInt
                     ;  Overload;
    function ReadData(var Buffer: WideChar) : NativeInt;  Overload;
    function ReadData(var Buffer: WideChar; Count: NativeInt) : NativeInt
                     ;  Overload;
    function ReadData(var Buffer: Int8) : NativeInt;  Overload;
    function ReadData(var Buffer: Int8; Count: NativeInt) : NativeInt
                     ;  Overload;
    function ReadData(var Buffer: UInt8) : NativeInt;  Overload;
    function ReadData(var Buffer: UInt8; Count: NativeInt) : NativeInt
                     ;  Overload;
    function ReadData(var Buffer: Int16) : NativeInt;  Overload;
    function ReadData(var Buffer: Int16; Count: NativeInt) : NativeInt
                     ;  Overload;
    function ReadData(var Buffer: UInt16) : NativeInt;  Overload;
    function ReadData(var Buffer: UInt16; Count: NativeInt) : NativeInt
                     ;  Overload;
    function ReadData(var Buffer: Int32) : NativeInt;  Overload;
    function ReadData(var Buffer: Int32; Count: NativeInt) : NativeInt
                     ;  Overload;
    function ReadData(var Buffer: UInt32) : NativeInt;  Overload;
    function ReadData(var Buffer: UInt32; Count: NativeInt) : NativeInt
                     ;  Overload;
    function ReadData(var Buffer: Int64) : NativeInt;  Overload;
    function ReadData(var Buffer: Int64; Count: NativeInt) : NativeInt
                     ;  Overload;
    function ReadData(var Buffer: UInt64) : NativeInt;  Overload;
    function ReadData(var Buffer: UInt64; Count: NativeInt) : NativeInt
                     ;  Overload;
    function ReadData(var Buffer: Single) : NativeInt;  Overload;
    function ReadData(var Buffer: Single; Count: NativeInt) : NativeInt
                     ;  Overload;
    function ReadData(var Buffer: Double) : NativeInt;  Overload;
    function ReadData(var Buffer: Double; Count: NativeInt) : NativeInt
                     ;  Overload;
    procedure ReadBuffer(var Buffer; Count: LongInt);
    procedure ReadBuffer(var Buffer: TBytes; Count: NativeInt);  Overload;
    procedure ReadBuffer(var Buffer: TBytes; Offset: NativeInt; 
                        Count: NativeInt);  Overload;
    procedure ReadBufferData(var Buffer: Boolean);  Overload;
    procedure ReadBufferData(var Buffer: Boolean; Count: NativeInt)
                            ;  Overload;
    procedure ReadBufferData(var Buffer: AnsiChar);  Overload;
    procedure ReadBufferData(var Buffer: AnsiChar; Count: NativeInt)
                            ;  Overload;
    procedure ReadBufferData(var Buffer: WideChar);  Overload;
    procedure ReadBufferData(var Buffer: WideChar; Count: NativeInt)
                            ;  Overload;
    procedure ReadBufferData(var Buffer: Int8);  Overload;
    procedure ReadBufferData(var Buffer: Int8; Count: NativeInt);  Overload;
    procedure ReadBufferData(var Buffer: UInt8);  Overload;
    procedure ReadBufferData(var Buffer: UInt8; Count: NativeInt);  Overload;
    procedure ReadBufferData(var Buffer: Int16);  Overload;
    procedure ReadBufferData(var Buffer: Int16; Count: NativeInt);  Overload;
    procedure ReadBufferData(var Buffer: UInt16);  Overload;
    procedure ReadBufferData(var Buffer: UInt16; Count: NativeInt)
                            ;  Overload;
    procedure ReadBufferData(var Buffer: Int32);  Overload;
    procedure ReadBufferData(var Buffer: Int32; Count: NativeInt);  Overload;
    procedure ReadBufferData(var Buffer: UInt32);  Overload;
    procedure ReadBufferData(var Buffer: UInt32; Count: NativeInt)
                            ;  Overload;
    procedure ReadBufferData(var Buffer: Int64);  Overload;
    procedure ReadBufferData(var Buffer: Int64; Count: NativeInt);  Overload;
    procedure ReadBufferData(var Buffer: UInt64);  Overload;
    procedure ReadBufferData(var Buffer: UInt64; Count: NativeInt)
                            ;  Overload;
    procedure ReadBufferData(var Buffer: Single);  Overload;
    procedure ReadBufferData(var Buffer: Single; Count: NativeInt)
                            ;  Overload;
    procedure ReadBufferData(var Buffer: Double);  Overload;
    procedure ReadBufferData(var Buffer: Double; Count: NativeInt)
                            ;  Overload;
    procedure WriteBuffer(const Buffer; Count: LongInt);
    procedure WriteBuffer(const Buffer: TBytes; Count: NativeInt);  Overload;
    procedure WriteBuffer(const Buffer: TBytes; Offset: NativeInt; 
                         Count: NativeInt);  Overload;
    function WriteData(const Buffer: TBytes; Count: NativeInt) : NativeInt
                      ;  Overload;
    function WriteData(const Buffer: Pointer; Count: NativeInt) : NativeInt
                      ;  Overload;
    function WriteData(const Buffer: Boolean) : NativeInt;  Overload;
    function WriteData(const Buffer: Boolean; Count: NativeInt) : NativeInt
                      ;  Overload;
    function WriteData(const Buffer: AnsiChar) : NativeInt;  Overload;
    function WriteData(const Buffer: AnsiChar; Count: NativeInt) : NativeInt
                      ;  Overload;
    function WriteData(const Buffer: WideChar) : NativeInt;  Overload;
    function WriteData(const Buffer: WideChar; Count: NativeInt) : NativeInt
                      ;  Overload;
    function WriteData(const Buffer: Int8) : NativeInt;  Overload;
    function WriteData(const Buffer: Int8; Count: NativeInt) : NativeInt
                      ;  Overload;
    function WriteData(const Buffer: UInt8) : NativeInt;  Overload;
    function WriteData(const Buffer: UInt8; Count: NativeInt) : NativeInt
                      ;  Overload;
    function WriteData(const Buffer: Int16) : NativeInt;  Overload;
    function WriteData(const Buffer: Int16; Count: NativeInt) : NativeInt
                      ;  Overload;
    function WriteData(const Buffer: UInt16) : NativeInt;  Overload;
    function WriteData(const Buffer: UInt16; Count: NativeInt) : NativeInt
                      ;  Overload;
    function WriteData(const Buffer: Int32) : NativeInt;  Overload;
    function WriteData(const Buffer: Int32; Count: NativeInt) : NativeInt
                      ;  Overload;
    function WriteData(const Buffer: UInt32) : NativeInt;  Overload;
    function WriteData(const Buffer: UInt32; Count: NativeInt) : NativeInt
                      ;  Overload;
    function WriteData(const Buffer: Int64) : NativeInt;  Overload;
    function WriteData(const Buffer: Int64; Count: NativeInt) : NativeInt
                      ;  Overload;
    function WriteData(const Buffer: UInt64) : NativeInt;  Overload;
    function WriteData(const Buffer: UInt64; Count: NativeInt) : NativeInt
                      ;  Overload;
    function WriteData(const Buffer: Single) : NativeInt;  Overload;
    function WriteData(const Buffer: Single; Count: NativeInt) : NativeInt
                      ;  Overload;
    function WriteData(const Buffer: Double) : NativeInt;  Overload;
    function WriteData(const Buffer: Double; Count: NativeInt) : NativeInt
                      ;  Overload;
    procedure WriteBufferData(Buffer: Int32);  Overload;
    procedure WriteBufferData(Buffer: Int32; Count: NativeInt);  Overload;
    procedure WriteBufferData(Buffer: Boolean);  Overload;
    procedure WriteBufferData(Buffer: Boolean; Count: NativeInt);  Overload;
    procedure WriteBufferData(Buffer: AnsiChar);  Overload;
    procedure WriteBufferData(Buffer: AnsiChar; Count: NativeInt);  Overload;
    procedure WriteBufferData(Buffer: WideChar);  Overload;
    procedure WriteBufferData(Buffer: WideChar; Count: NativeInt);  Overload;
    procedure WriteBufferData(Buffer: Int8);  Overload;
    procedure WriteBufferData(Buffer: Int8; Count: NativeInt);  Overload;
    procedure WriteBufferData(Buffer: UInt8);  Overload;
    procedure WriteBufferData(Buffer: UInt8; Count: NativeInt);  Overload;
    procedure WriteBufferData(Buffer: Int16);  Overload;
    procedure WriteBufferData(Buffer: Int16; Count: NativeInt);  Overload;
    procedure WriteBufferData(Buffer: UInt16);  Overload;
    procedure WriteBufferData(Buffer: UInt16; Count: NativeInt);  Overload;
    procedure WriteBufferData(Buffer: UInt32);  Overload;
    procedure WriteBufferData(Buffer: UInt32; Count: NativeInt);  Overload;
    procedure WriteBufferData(Buffer: Int64);  Overload;
    procedure WriteBufferData(Buffer: Int64; Count: NativeInt);  Overload;
    procedure WriteBufferData(Buffer: UInt64);  Overload;
    procedure WriteBufferData(Buffer: UInt64; Count: NativeInt);  Overload;
    procedure WriteBufferData(Buffer: Single);  Overload;
    procedure WriteBufferData(Buffer: Single; Count: NativeInt);  Overload;
    procedure WriteBufferData(Buffer: Double);  Overload;
    procedure WriteBufferData(Buffer: Double; Count: NativeInt);  Overload;
    function CopyFrom(Source: TStream; Count: Int64) : Int64;
    function ReadComponent(Instance: TComponent) : TComponent;
    function ReadComponentRes(Instance: TComponent) : TComponent;
    procedure WriteComponent(Instance: TComponent);
    procedure WriteComponentRes(const ResName: string; Instance: TComponent);
    procedure WriteDescendent(Instance: TComponent; Ancestor: TComponent);
    procedure WriteDescendentRes(const ResName: string; 
                                Instance: TComponent; Ancestor: TComponent);
    procedure WriteResourceHeader(const ResName: string; 
                                 var FixupInfo: LongInt);
    procedure FixupResourceHeader(FixupInfo: LongInt);
    procedure ReadResHeader;
    function ReadByte : Byte;
    function ReadWord : Word;
    function ReadDWord : Cardinal;
    function ReadQWord : QWord;
    function ReadAnsiString : string;
    procedure WriteByte(b: Byte);
    procedure WriteWord(w: Word);
    procedure WriteDWord(d: Cardinal);
    procedure WriteQWord(q: QWord);
    procedure WriteAnsiString(const S: string);  Virtual;
    Position : Int64;
    Size : Int64;
  end
  ;

Description

TStream is the base class for all streaming classes. It defines methods for reading , writing from and to streams, as well as functions to determine the size of the stream as well as the current position of the stream.

Descendant classes such as TMemoryStream or TFileStream then override these methods to write streams to memory or file.

Members

Member	Type	Visibility	Description
CopyFrom	Method	public	Copy data from one stream to another
Discard	Method	protected
DiscardLarge	Method	protected
FakeSeekForward	Method	protected
FixupResourceHeader	Method	public	Not implemented in FPC
GetPosition	Method	protected
GetSize	Method	protected
InvalidSeek	Method	protected
Position	Property	public	The current position in the stream.
Read	Method	public	Reads data from the stream to a buffer and returns the number of bytes read.
ReadAnsiString	Method	public	Read an ansistring from the stream and return its value.
ReadBuffer	Method	public	Reads data from the stream to a buffer
ReadBufferData	Method	public
ReadByte	Method	public	Read a byte from the stream and return its value.
ReadComponent	Method	public	Reads component data from a stream
ReadComponentRes	Method	public	Reads component data and resource header from a stream
ReadData	Method	public
ReadDWord	Method	public	Read a DWord from the stream and return its value.
ReadExactSizeData	Method	protected
ReadMaxSizeData	Method	protected
ReadNotImplemented	Method	protected
ReadQWord	Method	public	Read a QWord value from the stream and return its value
ReadResHeader	Method	public	Read a resource header from the stream.
ReadWord	Method	public	Read a word from the stream and return its value.
Seek	Method	public	Sets the current position in the stream
SetPosition	Method	protected
SetSize	Method	protected	Sets the size of the stream
SetSize64	Method	protected
Size	Property	public	The current size of the stream.
Write	Method	public	Writes data from a buffer to the stream and returns the number of bytes written.
WriteAnsiString	Method	public	Write an ansistring to the stream.
WriteBuffer	Method	public	Writes data from a buffer to the stream
WriteBufferData	Method	public
WriteByte	Method	public	Write a byte to the stream.
WriteComponent	Method	public	Write component data to the stream
WriteComponentRes	Method	public	Write resource header and component data to a stream
WriteData	Method	public
WriteDescendent	Method	public	Write descendent of a component
WriteDescendentRes	Method	public	Write descendent of a component as resource
WriteDWord	Method	public	Write a DWord to the stream.
WriteExactSizeData	Method	protected
WriteMaxSizeData	Method	protected
WriteNotImplemented	Method	protected
WriteQWord	Method	public	Write a QWord value to the stream
WriteResourceHeader	Method	public	Write resource header to the stream
WriteWord	Method	public	Write a word to the stream.

Inheritance

Class	Description
TStream	Base class for streams.

Name	Description
Int64	64-bit, signed integer
Int64	64-bit, signed integer
TFileStream	Stream that stores its data in a named file on disk.
TMemoryStream	Standard implementation of a stream that stores its data in memory
TStringStream	Stream that stores its data in a string.

TStream

Declaration

Description

Members

Inheritance

See also