BinaryWriter Constructors

Definition

Namespace:

System.IO

Assembly:

System.Runtime.dll

Initializes a new instance of the BinaryWriter class that writes to a stream.

Overloads

BinaryWriter()	Initializes a new instance of the BinaryWriter class that writes to a stream.
BinaryWriter(Stream)	Initializes a new instance of the BinaryWriter class based on the specified stream and using UTF-8 encoding.
BinaryWriter(Stream, Encoding)	Initializes a new instance of the BinaryWriter class based on the specified stream and character encoding.
BinaryWriter(Stream, Encoding, Boolean)	Initializes a new instance of the BinaryWriter class based on the specified stream and character encoding, and optionally leaves the stream open.

BinaryWriter()

Source:

BinaryWriter.cs

Initializes a new instance of the BinaryWriter class that writes to a stream.

protected:
 BinaryWriter();

protected BinaryWriter ();

Protected Sub New ()

Remarks

For a list of common I/O tasks, see Common I/O Tasks.

See also

• File and Stream I/O
• How to: Read Text from a File
• How to: Write Text to a File

BinaryWriter(Stream)

Source:

BinaryWriter.cs

Initializes a new instance of the BinaryWriter class based on the specified stream and using UTF-8 encoding.

public:
 BinaryWriter(System::IO::Stream ^ output);

public BinaryWriter (System.IO.Stream output);

new System.IO.BinaryWriter : System.IO.Stream -> System.IO.BinaryWriter

Public Sub New (output As Stream)

Parameters

output

Stream

The output stream.

Exceptions

ArgumentException

The stream does not support writing or is already closed.

ArgumentNullException

output is null.

Examples

The following code example demonstrates how to store and retrieve application settings in a file.

using System;
using System.IO;
using System.Text;

class ConsoleApplication
{
    const string fileName = "AppSettings.dat";

    static void Main()
    {
        WriteDefaultValues();
        DisplayValues();
    }

    public static void WriteDefaultValues()
    {
        using (var stream = File.Open(fileName, FileMode.Create))
        {
            using (var writer = new BinaryWriter(stream, Encoding.UTF8, false))
            {
                writer.Write(1.250F);
                writer.Write(@"c:\Temp");
                writer.Write(10);
                writer.Write(true);
            }
        }
    }

    public static void DisplayValues()
    {
        float aspectRatio;
        string tempDirectory;
        int autoSaveTime;
        bool showStatusBar;

        if (File.Exists(fileName))
        {
            using (var stream = File.Open(fileName, FileMode.Open))
            {
                using (var reader = new BinaryReader(stream, Encoding.UTF8, false))
                {
                    aspectRatio = reader.ReadSingle();
                    tempDirectory = reader.ReadString();
                    autoSaveTime = reader.ReadInt32();
                    showStatusBar = reader.ReadBoolean();
                }
            }

            Console.WriteLine("Aspect ratio set to: " + aspectRatio);
            Console.WriteLine("Temp directory is: " + tempDirectory);
            Console.WriteLine("Auto save time set to: " + autoSaveTime);
            Console.WriteLine("Show status bar: " + showStatusBar);
        }
    }
}

open System.IO
open System.Text

let fileName = "AppSettings.dat"

let writeDefaultValues () =
    use stream = File.Open(fileName, FileMode.Create)
    use writer = new BinaryWriter(stream, Encoding.UTF8, false)
    writer.Write 1.250F
    writer.Write @"c:\Temp"
    writer.Write 10
    writer.Write true

let displayValues () =
    if File.Exists fileName then
        use stream = File.Open(fileName, FileMode.Open)
        use reader = new BinaryReader(stream, Encoding.UTF8, false)
        let aspectRatio = reader.ReadSingle()
        let tempDirectory = reader.ReadString()
        let autoSaveTime = reader.ReadInt32()
        let showStatusBar = reader.ReadBoolean()

        printfn $"Aspect ratio set to: {aspectRatio}"
        printfn $"Temp directory is: {tempDirectory}"
        printfn $"Auto save time set to: {autoSaveTime}"
        printfn $"Show status bar: {showStatusBar}"

writeDefaultValues ()
displayValues ()

Imports System.IO

Module Module1
    Const fileName As String = "AppSettings.dat"

    Sub Main()
        WriteDefaultValues()
        DisplayValues()
    End Sub

    Sub WriteDefaultValues()
        Using writer As BinaryWriter = New BinaryWriter(File.Open(fileName, FileMode.Create))
            writer.Write(1.25F)
            writer.Write("c:\Temp")
            writer.Write(10)
            writer.Write(True)
        End Using
    End Sub

    Sub DisplayValues()
        Dim aspectRatio As Single
        Dim tempDirectory As String
        Dim autoSaveTime As Integer
        Dim showStatusBar As Boolean

        If (File.Exists(fileName)) Then

            Using reader As BinaryReader = New BinaryReader(File.Open(fileName, FileMode.Open))
                aspectRatio = reader.ReadSingle()
                tempDirectory = reader.ReadString()
                autoSaveTime = reader.ReadInt32()
                showStatusBar = reader.ReadBoolean()
            End Using

            Console.WriteLine("Aspect ratio set to: " & aspectRatio)
            Console.WriteLine("Temp directory is: " & tempDirectory)
            Console.WriteLine("Auto save time set to: " & autoSaveTime)
            Console.WriteLine("Show status bar: " & showStatusBar)
        End If
    End Sub

End Module

Remarks

For a list of common I/O tasks, see Common I/O Tasks.

See also

• UTF8
• File and Stream I/O
• How to: Read Text from a File
• How to: Write Text to a File

BinaryWriter(Stream, Encoding)

Source:

BinaryWriter.cs

Initializes a new instance of the BinaryWriter class based on the specified stream and character encoding.

public:
 BinaryWriter(System::IO::Stream ^ output, System::Text::Encoding ^ encoding);

public BinaryWriter (System.IO.Stream output, System.Text.Encoding encoding);

new System.IO.BinaryWriter : System.IO.Stream * System.Text.Encoding -> System.IO.BinaryWriter

Public Sub New (output As Stream, encoding As Encoding)

Parameters

output

Stream

The output stream.

encoding

Encoding

The character encoding to use.

Exceptions

ArgumentException

The stream does not support writing or is already closed.

ArgumentNullException

output or encoding is null.

Remarks

For a list of common I/O tasks, see Common I/O Tasks.

See also

• Encoding
• File and Stream I/O
• How to: Read Text from a File
• How to: Write Text to a File

BinaryWriter(Stream, Encoding, Boolean)

Source:

BinaryWriter.cs

Initializes a new instance of the BinaryWriter class based on the specified stream and character encoding, and optionally leaves the stream open.

public:
 BinaryWriter(System::IO::Stream ^ output, System::Text::Encoding ^ encoding, bool leaveOpen);

public BinaryWriter (System.IO.Stream output, System.Text.Encoding encoding, bool leaveOpen);

new System.IO.BinaryWriter : System.IO.Stream * System.Text.Encoding * bool -> System.IO.BinaryWriter

Public Sub New (output As Stream, encoding As Encoding, leaveOpen As Boolean)

Parameters

output

Stream

The output stream.

encoding

Encoding

The character encoding to use.

leaveOpen

Boolean

true to leave the stream open after the BinaryWriter object is disposed; otherwise, false.

Exceptions

ArgumentException

The stream does not support writing or is already closed.

ArgumentNullException

output or encoding is null.

See also

• Encoding
• File and Stream I/O
• How to: Read Text from a File
• How to: Write Text to a File