StreamWriter Class

[ This article is for Windows Phone 8 developers. If you’re developing for Windows 10, see the latest documentation. ]

Implements a TextWriter for writing characters to a stream in a particular encoding.

Inheritance Hierarchy

System..::.Object
System.IO..::.TextWriter
System.IO..::.StreamWriter

Namespace: System.IO
Assembly: mscorlib (in mscorlib.dll)

Syntax

Public Class StreamWriter _
    Inherits TextWriter
public class StreamWriter : TextWriter

The StreamWriter type exposes the following members.

Constructors

Name Description
StreamWriter(Stream) Initializes a new instance of the StreamWriter class for the specified stream, using UTF-8 encoding and the default buffer size.
StreamWriter(String) Initializes a new instance of the StreamWriter class for the specified file on the specified path, using the default encoding and buffer size.
StreamWriter(Stream, Encoding) Initializes a new instance of the StreamWriter class for the specified stream, using the specified encoding and the default buffer size.
StreamWriter(String, Boolean) Initializes a new instance of the StreamWriter class for the specified file on the specified path, using the default encoding and buffer size. If the file exists, it can be either overwritten or appended to. If the file does not exist, this constructor creates a new file.
StreamWriter(Stream, Encoding, Int32) Initializes a new instance of the StreamWriter class for the specified stream, using the specified encoding and buffer size.
StreamWriter(String, Boolean, Encoding) Initializes a new instance of the StreamWriter class for the specified file on the specified path, using the specified encoding and default buffer size. If the file exists, it can be either overwritten or appended to. If the file does not exist, this constructor creates a new file.
StreamWriter(Stream, Encoding, Int32, Boolean) Initializes a new instance of the StreamWriter class for the specified stream, using the specified encoding, buffer size, and a value that specifies whether to leave the stream open.
StreamWriter(String, Boolean, Encoding, Int32) Initializes a new instance of the StreamWriter class for the specified file on the specified path, using the specified encoding and buffer size. If the file exists, it can be either overwritten or appended to. If the file does not exist, this constructor creates a new file.

Top

Properties

Name Description
AutoFlush Gets or sets a value indicating whether the StreamWriter will flush its buffer to the underlying stream after every call to StreamWriter..::.Write.
BaseStream Gets the underlying stream that interfaces with a backing store.
Encoding Gets the Encoding in which the output is written. (Overrides TextWriter..::.Encoding.)
FormatProvider Gets an object that controls formatting. (Inherited from TextWriter.)
NewLine Gets or sets the line terminator string used by the current TextWriter. (Inherited from TextWriter.)

Top

Methods

Name Description
Close Closes the current StreamWriter object and the underlying stream. (Overrides TextWriter..::.Close()()().)
Dispose()()() Releases all resources used by the TextWriter object. (Inherited from TextWriter.)
Dispose(Boolean) Releases the unmanaged resources used by the StreamWriter and optionally releases the managed resources. (Overrides TextWriter..::.Dispose(Boolean).)
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 the Object 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 stream. (Overrides TextWriter..::.Flush()()().)
FlushAsync Clears all buffers for this stream asynchronously and causes any buffered data to be written to the underlying device. (Overrides TextWriter..::.FlushAsync()()().)
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.)
ToString Returns a string that represents the current object. (Inherited from Object.)
Write(Boolean) Writes the text representation of a Boolean value to the text stream. (Inherited from TextWriter.)
Write(Char) Writes a character to the stream. (Overrides TextWriter..::.Write(Char).)
Write(array<Char>[]()[]) Writes a character array to the stream. (Overrides TextWriter..::.Write(array<Char>[]()[]).)
Write(Decimal) Writes the text representation of a decimal value to the text stream. (Inherited from TextWriter.)
Write(Double) Writes the text representation of an 8-byte floating-point value to the text stream. (Inherited from TextWriter.)
Write(Int32) Writes the text representation of a 4-byte signed integer to the text stream. (Inherited from TextWriter.)
Write(Int64) Writes the text representation of an 8-byte signed integer to the text stream. (Inherited from TextWriter.)
Write(Object) Writes the text representation of an object to the text stream by calling ToString on that object. (Inherited from TextWriter.)
Write(Single) Writes the text representation of a 4-byte floating-point value to the text stream. (Inherited from TextWriter.)
Write(String) Writes a string to the stream. (Overrides TextWriter..::.Write(String).)
Write(UInt32) Writes the text representation of a 4-byte unsigned integer to the text stream. (Inherited from TextWriter.)
Write(UInt64) Writes the text representation of an 8-byte unsigned integer to the text stream. (Inherited from TextWriter.)
Write(String, Object) Writes out a formatted string, using the same semantics as String..::.Format. (Inherited from TextWriter.)
Write(String, array<Object>[]()[]) Writes out a formatted string, using the same semantics as String..::.Format. (Inherited from TextWriter.)
Write(array<Char>[]()[], Int32, Int32) Writes a subarray of characters to the stream. (Overrides TextWriter..::.Write(array<Char>[]()[], Int32, Int32).)
Write(String, Object, Object) Writes out a formatted string, using the same semantics as String..::.Format. (Inherited from TextWriter.)
WriteAsync(Char) Writes a character to the stream asynchronously. (Overrides TextWriter..::.WriteAsync(Char).)
WriteAsync(array<Char>[]()[]) Writes a character array to the text string or stream asynchronously. (Inherited from TextWriter.)
WriteAsync(String) Writes a string to the stream asynchronously. (Overrides TextWriter..::.WriteAsync(String).)
WriteAsync(array<Char>[]()[], Int32, Int32) Writes a subarray of characters to the stream asynchronously. (Overrides TextWriter..::.WriteAsync(array<Char>[]()[], Int32, Int32).)
WriteLine()()() Writes a line terminator to the text stream. (Inherited from TextWriter.)
WriteLine(Boolean) Writes the text representation of a Boolean followed by a line terminator to the text stream. (Inherited from TextWriter.)
WriteLine(Char) Writes a character followed by a line terminator to the text stream. (Inherited from TextWriter.)
WriteLine(array<Char>[]()[]) Writes an array of characters followed by a line terminator to the text stream. (Inherited from TextWriter.)
WriteLine(Decimal) Writes the text representation of a decimal value followed by a line terminator to the text stream. (Inherited from TextWriter.)
WriteLine(Double) Writes the text representation of a 8-byte floating-point value followed by a line terminator to the text stream. (Inherited from TextWriter.)
WriteLine(Int32) Writes the text representation of a 4-byte signed integer followed by a line terminator to the text stream. (Inherited from TextWriter.)
WriteLine(Int64) Writes the text representation of an 8-byte signed integer followed by a line terminator to the text stream. (Inherited from TextWriter.)
WriteLine(Object) Writes the text representation of an object by calling ToString on this object, followed by a line terminator to the text stream. (Inherited from TextWriter.)
WriteLine(Single) Writes the text representation of a 4-byte floating-point value followed by a line terminator to the text stream. (Inherited from TextWriter.)
WriteLine(String) Writes a string followed by a line terminator to the text stream. (Inherited from TextWriter.)
WriteLine(UInt32) Writes the text representation of a 4-byte unsigned integer followed by a line terminator to the text stream. (Inherited from TextWriter.)
WriteLine(UInt64) Writes the text representation of an 8-byte unsigned integer followed by a line terminator to the text stream. (Inherited from TextWriter.)
WriteLine(String, Object) Writes out a formatted string and a new line, using the same semantics as Format. (Inherited from TextWriter.)
WriteLine(String, array<Object>[]()[]) Writes out a formatted string and a new line, using the same semantics as Format. (Inherited from TextWriter.)
WriteLine(array<Char>[]()[], Int32, Int32) Writes a subarray of characters followed by a line terminator to the text stream. (Inherited from TextWriter.)
WriteLine(String, Object, Object) Writes out a formatted string and a new line, using the same semantics as Format. (Inherited from TextWriter.)
WriteLineAsync()()() Writes a line terminator asynchronously to the stream. (Overrides TextWriter..::.WriteLineAsync()()().)
WriteLineAsync(Char) Writes a character followed by a line terminator asynchronously to the stream. (Overrides TextWriter..::.WriteLineAsync(Char).)
WriteLineAsync(array<Char>[]()[]) Writes an array of characters followed by a line terminator asynchronously to the text string or stream. (Inherited from TextWriter.)
WriteLineAsync(String) Writes a string followed by a line terminator asynchronously to the stream. (Overrides TextWriter..::.WriteLineAsync(String).)
WriteLineAsync(array<Char>[]()[], Int32, Int32) Writes a subarray of characters followed by a line terminator asynchronously to the stream. (Overrides TextWriter..::.WriteLineAsync(array<Char>[]()[], Int32, Int32).)

Top

Fields

Name Description
CoreNewLine Stores the new line characters used for this TextWriter. (Inherited from TextWriter.)
Null Provides a StreamWriter with no backing store that can be written to, but not read from.

Top

Remarks

StreamWriter is designed for character output in a particular Encoding, whereas classes derived from Stream are designed for byte input and output.

StreamWriter defaults to using an instance of UTF8Encoding unless specified otherwise. This instance of UTF8Encoding is constructed without a Byte-Order Mark (BOM), so its GetPreamble method returns an empty byte array. To create a StreamWriter using UTF-8 encoding and a BOM, consider using a constructor that specifies encoding, such as StreamWriter(String, Boolean, Encoding).

By default, a StreamWriter is not thread safe.

Examples

The following example uses a StreamWriter to save the contents of a text box control (named inputData) to a file in the user's My Documents folder. For an example of how to read the contents of the file, see the StreamReader class.

Private Sub SaveFile_Click(ByVal sender As Object, ByVal e As RoutedEventArgs)



        ' fileLoc is a global string variable, set in StreamReader example.
        Using sw As New StreamWriter(fileLoc, False)
            sw.WriteLine(inputData.Text)
            inputData.Text = ""
            inputData.Visibility = Visibility.Collapsed
        End Using

End Sub
private void SaveFile_Click(object sender, RoutedEventArgs e)
{
    // fileLoc is a global string variable, set in StreamReader example.
    using (StreamWriter sw = new StreamWriter(fileLoc, false))
    {
        sw.WriteLine(inputData.Text);
        inputData.Text = "";
        inputData.Visibility = Visibility.Collapsed;
    }

}

Version Information

Windows Phone OS

Supported in: 8.1, 8.0, 7.1, 7.0

Platforms

Windows Phone

Thread Safety

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

See Also

Reference

System.IO Namespace

StreamReader