| Description |
If the current stream has not been exhausted, the next byte is returned as a signed byte (value ranges from -128 to +127).
The stream position is updated accordingly.
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| Microsoft MSDN Links |
System.IO
System.IO.BinaryReader
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| Reading a single signed byte at a time |
// Full Unit code.
// -------------------------------------------------------------
// Create a new WinForm application, double click the form to
// create an OnLoad event, and then replace the WinForm unit
// with this text.
unit WinForm;
interface
uses
System.Drawing, System.Collections, System.ComponentModel,
System.Windows.Forms, System.Data;
type
TWinForm = class(System.Windows.Forms.Form)
\{REGION 'Designer Managed Code'\} // Note that REGION and ENREGION should be prefixed by a dollar sign
strict private
///
/// Required designer variable.
///
Components: System.ComponentModel.Container;
///
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
///
procedure InitializeComponent;
procedure TWinForm_Load(sender: System.Object; e: System.EventArgs);
{ENDREGION}
strict protected
///
/// Clean up any resources being used.
///
procedure Dispose(Disposing: Boolean); override;
private
{ Private Declarations }
public
constructor Create;
end;
[assembly: RuntimeRequiredAttribute(TypeOf(TWinForm))]
implementation
\{REGION 'Windows Form Designer generated code'\}
///
/// Required method for Designer support -- do not modify
/// the contents of this method with the code editor.
///
procedure TWinForm.InitializeComponent;
begin
//
// TWinForm
//
Self.AutoScaleBaseSize := System.Drawing.Size.Create(5, 13);
Self.ClientSize := System.Drawing.Size.Create(292, 266);
Self.Name := 'TWinForm';
Self.Text := 'WinForm';
Include(Self.Load, Self.TWinForm_Load);
end;
{ENDREGION}
procedure TWinForm.Dispose(Disposing: Boolean);
begin
if Disposing then
begin
if Components <> nil then
Components.Dispose();
end;
inherited Dispose(Disposing);
end;
constructor TWinForm.Create;
begin
inherited Create;
//
// Required for Windows Form Designer support
//
InitializeComponent;
//
// TODO: Add any constructor code after InitializeComponent call
//
end;
procedure TWinForm.TWinForm_Load(sender: System.Object; e: System.EventArgs);
program Project1;
{$APPTYPE CONSOLE}
uses
System.IO;
var
MyFileStream : System.IO.FileStream;
MyFileWriter : System.IO.BinaryWriter;
MyFileReader : System.IO.BinaryReader;
SignedByte : SByte;
begin
// Create and open our binary file as a stream
MyFileStream := System.IO.File.Open('C:DelphiBasics.txt',
System.IO.FileMode.Create);
// Create a BinaryWriter to allow writing to this file
MyFileWriter := System.IO.BinaryWriter.Create(MyFileStream);
// Write to the file
MyFileWriter.Write(12);
MyFileWriter.Write(-34);
MyFileWriter.Write('ABC'); // Chr(65) Chr(66) Chr(67)
// Close the writer and the stream
MyFileWriter.Close;
MyFileStream.Close;
// Reopen the stream for reading
MyFileStream := System.IO.File.Open('C:DelphiBasics.txt',
System.IO.FileMode.Open);
// Create a BinaryReader to allow the file to be read back
MyFileReader := System.IO.BinaryReader.Create(MyFileStream);
// Display the file contents
try
// Infinite loop - we rely on the exception for file end
while 1 = 1 do
begin
SignedByte := MyFileReader.ReadSByte;
Console.WriteLine(SignedByte.ToString);
end;
except
On E : EndOfStreamException do
Console.WriteLine('File display completed');
end;
// Close the reader and the stream
MyFileReader.Close;
MyFileStream.Close;
Console.Readline;
end.
end. | | Hide full unit code | 12
-34
3
65
66
67
File display completed
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