Encoder.GetBytes Method (Char[], Int32, Int32, Byte[], Int32, Boolean)

When overridden in a derived class, encodes a set of characters from the specified character array and any characters in the internal buffer into the specified byte array. A parameter indicates whether to clear the internal state of the encoder after the conversion.

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

public abstract int GetBytes(
	char[] chars,
	int charIndex,
	int charCount,
	byte[] bytes,
	int byteIndex,
	bool flush


Type: System.Char[]
The character array containing the set of characters to encode.
Type: System.Int32
The zero-based index of the first character to encode.
Type: System.Int32
The number of characters to encode.
Type: System.Byte[]
The byte array to contain the resulting sequence of bytes.
Type: System.Int32
The zero-based index at which to start writing the resulting sequence of bytes.
Type: System.Boolean
true to clear the internal state of the encoder after the conversion; otherwise, false.

Return Value

Type: System.Int32
The actual number of bytes written into bytes.


chars is null.


bytes is null.


charIndex or charCount or byteIndex is less than zero.


charIndex and charCount do not denote a valid range in chars.


byteIndex is not a valid index in bytes.


bytes does not have enough capacity from byteIndex to the end of the array to accommodate the resulting bytes.


A fallback occurred (see Understanding Encodings for fuller explanation).

The Encoder object saves state between calls to GetBytes. When the application is done with a stream of data, it should set the flush parameter to true in the last call to GetBytes to make sure that the state information is flushed and that the encoded bytes are properly terminated. With this setting, the encoder ignores invalid bytes at the end of the data block, such as unmatched surrogates or incomplete combining sequences, and clears the internal buffer.

To calculate the exact buffer size that GetBytes requires to store the resulting characters, call the GetByteCount method.

If GetBytes is called with flush set to false, the encoder stores trailing bytes at the end of the data block in an internal buffer and uses them in the next encoding operation. The application should call GetByteCount on a block of data immediately before calling GetBytes on the same block, so that any trailing characters from the previous block are included in the calculation.

The following example demonstrates how to encode a range of elements from a character array and store the encoded bytes in a range of elements in a byte array. The GetByteCount method is used to determine the size of the array required by GetBytes.

using System;
using System.Text;

class Example
   public static void Demo(System.Windows.Controls.TextBlock outputBlock)
      Byte[] bytes;
      // Unicode characters.
      Char[] chars = new Char[] {
            '\u0023', // #
            '\u0025', // %
            '\u03a0', // Pi
            '\u03a3'  // Sigma

      Encoder uniEncoder = Encoding.Unicode.GetEncoder();

      int byteCount = uniEncoder.GetByteCount(chars, 0, chars.Length, true);
      bytes = new Byte[byteCount];
      int bytesEncodedCount = uniEncoder.GetBytes(chars, 0, chars.Length, bytes, 0, true);

      outputBlock.Text += String.Format(
          "{0} bytes used to encode characters.", bytesEncodedCount
      ) + "\n";

      outputBlock.Text += "Encoded bytes: ";
      foreach (Byte b in bytes)
         outputBlock.Text += String.Format("[{0}]", b);
      outputBlock.Text += "\n";


Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

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