BinaryWriter Class
Writes primitive types in binary to a stream and supports writing strings in a specific encoding.
Namespace: System.IO
Assembly: mscorlib (in mscorlib.dll)
The BinaryWriter type exposes the following members.
| Name | Description | |
|---|---|---|
![]() ![]() ![]() ![]() | 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. |
| Name | Description | |
|---|---|---|
![]() ![]() | Close | Closes the current BinaryWriter and the underlying stream. |
![]() ![]() ![]() | Dispose() | Releases all resources used by the current instance of the BinaryWriter class. |
![]() ![]() ![]() ![]() | Dispose(Boolean) | Releases the unmanaged resources used by the BinaryWriter and optionally releases the managed resources. |
![]() ![]() ![]() ![]() | Equals(Object) | Determines whether the specified object is equal to the current object. (Inherited from Object.) |
![]() ![]() ![]() ![]() | Finalize | Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.) |
![]() ![]() ![]() ![]() | Flush | Clears all buffers for the current writer and causes any buffered data to be written to the underlying device. |
![]() ![]() ![]() ![]() | GetHashCode | Serves as a hash function for a particular type. (Inherited from Object.) |
![]() ![]() ![]() ![]() | GetType | Gets the Type of the current instance. (Inherited from Object.) |
![]() ![]() ![]() ![]() | MemberwiseClone | Creates a shallow copy of the current Object. (Inherited from Object.) |
![]() ![]() ![]() ![]() | Seek | Sets the position within the current stream. |
![]() ![]() ![]() ![]() | ToString | Returns a string that represents the current object. (Inherited from Object.) |
![]() ![]() ![]() ![]() | Write(Boolean) | Writes a one-byte Boolean value to the current stream, with 0 representing false and 1 representing true. |
![]() ![]() ![]() ![]() | Write(Byte) | Writes an unsigned byte to the current stream and advances the stream position by one byte. |
![]() ![]() ![]() ![]() | Write(Byte[]) | Writes a byte array to the underlying stream. |
![]() ![]() ![]() ![]() | Write(Char) | Writes a Unicode character to the current stream and advances the current position of the stream in accordance with the Encoding used and the specific characters being written to the stream. |
![]() ![]() ![]() ![]() | Write(Char[]) | Writes a character array to the current stream and advances the current position of the stream in accordance with the Encoding used and the specific characters being written to the stream. |
![]() ![]() ![]() ![]() | Write(Decimal) | Writes a decimal value to the current stream and advances the stream position by sixteen bytes. |
![]() ![]() ![]() ![]() | Write(Double) | Writes an eight-byte floating-point value to the current stream and advances the stream position by eight bytes. |
![]() ![]() ![]() ![]() | Write(Int16) | Writes a two-byte signed integer to the current stream and advances the stream position by two bytes. |
![]() ![]() ![]() ![]() | Write(Int32) | Writes a four-byte signed integer to the current stream and advances the stream position by four bytes. |
![]() ![]() ![]() ![]() | Write(Int64) | Writes an eight-byte signed integer to the current stream and advances the stream position by eight bytes. |
![]() ![]() ![]() ![]() | Write(SByte) | Writes a signed byte to the current stream and advances the stream position by one byte. |
![]() ![]() ![]() ![]() | Write(Single) | Writes a four-byte floating-point value to the current stream and advances the stream position by four bytes. |
![]() ![]() ![]() ![]() | Write(String) | Writes a length-prefixed string to this stream in the current encoding of the BinaryWriter, and advances the current position of the stream in accordance with the encoding used and the specific characters being written to the stream. |
![]() ![]() ![]() ![]() | Write(UInt16) | Writes a two-byte unsigned integer to the current stream and advances the stream position by two bytes. |
![]() ![]() ![]() ![]() | Write(UInt32) | Writes a four-byte unsigned integer to the current stream and advances the stream position by four bytes. |
![]() ![]() ![]() ![]() | Write(UInt64) | Writes an eight-byte unsigned integer to the current stream and advances the stream position by eight bytes. |
![]() ![]() ![]() ![]() | Write(Byte[], Int32, Int32) | Writes a region of a byte array to the current stream. |
![]() ![]() ![]() ![]() | Write(Char[], Int32, Int32) | Writes a section of a character array to the current stream, and advances the current position of the stream in accordance with the Encoding used and perhaps the specific characters being written to the stream. |
![]() ![]() ![]() ![]() | Write7BitEncodedInt | Writes a 32-bit integer in a compressed format. |
| Name | Description | |
|---|---|---|
![]() ![]() ![]() | IDisposable.Dispose | Performs application-defined tasks associated with freeing, releasing, or resetting unmanaged resources. |
The BinaryWriter class provides methods that simplify writing primitive data types to a stream. For example, you can use the Write method to write a Boolean value to the stream as a one-byte value. The class includes write methods that support different data types.
When you create a new instance of the BinaryWriter class, you provide the stream to write to, and optionally specify the type of encoding and whether to leave the stream open after disposing the BinaryWriter object. If you do not specify an encoding type, UTF-8 is used.
A derived class can override the methods of this class to give unique character encodings.
The following code example demonstrates how to store and retrieve application settings in a file.
using System; using System.IO; class ConsoleApplication { const string fileName = "AppSettings.dat"; static void Main() { WriteDefaultValues(); DisplayValues(); } public static void WriteDefaultValues() { using (BinaryWriter writer = new BinaryWriter(File.Open(fileName, FileMode.Create))) { 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 (BinaryReader reader = new BinaryReader(File.Open(fileName, FileMode.Open))) { 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); } } }
Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.










