UnicodeEncoding.GetBytes Method (Char(), Int32, Int32, Byte(), Int32)
[ This article is for Windows Phone 8 developers. If you’re developing for Windows 10, see the latest documentation. ]
Encodes a set of characters from the specified character array into the specified byte array.
Assembly: mscorlib (in mscorlib.dll)
'Declaration Public Overrides Function GetBytes ( _ chars As Char(), _ charIndex As Integer, _ charCount As Integer, _ bytes As Byte(), _ byteIndex As Integer _ ) As Integer
Parameters
- chars
- Type:
System.Char
()
The character array containing the set of characters to encode.
- charIndex
- Type: System.Int32
The zero-based index of the first character to encode.
- charCount
- Type: System.Int32
The number of characters to encode.
- bytes
- Type:
System.Byte
()
The byte array to contain the resulting sequence of bytes.
- byteIndex
- Type: System.Int32
The zero-based index at which to start writing the resulting sequence of bytes.
| Exception | Condition |
|---|---|
| ArgumentNullException | chars is null (Nothing). -or- bytes is null (Nothing). |
| ArgumentOutOfRangeException | charIndex or charCount or byteIndex is less than zero. -or- charIndex and charCount do not denote a valid range in chars. -or- byteIndex is not a valid index in bytes. |
| ArgumentException | Error detection is enabled, and chars contains an invalid sequence of characters. -or- bytes does not have enough capacity from byteIndex to the end of the array to accommodate the resulting bytes. |
| EncoderFallbackException | A fallback occurred. |
To calculate the exact array size required by GetBytes to store the resulting bytes, call the GetByteCount method. To calculate the maximum array size, call the GetMaxByteCount method. The GetByteCount method generally allocates less memory, while the GetMaxByteCount method generally executes faster.
With error detection, an invalid sequence causes this method to throw a ArgumentException. Without error detection, invalid sequences are ignored, and no exception is thrown.
Data to be converted, such as data read from a stream, might be available only in sequential blocks. In this case, or if the amount of data is so large that it needs to be divided into smaller blocks, the application should use the Decoder or the Encoder provided by the GetDecoder method or the GetEncoder method, respectively.
Note: |
|---|
To ensure that the encoded bytes are decoded properly, the application should prefix encoded bytes with a preamble. |
The following code example demonstrates how to use the GetBytes method to encode a range of characters from a String and store the encoded bytes in a range of elements in a byte array.
Imports System.Text Class Example Public Shared Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock) Dim bytes() As Byte Dim chars As String = "Unicode Encoding Example" Dim uni As New UnicodeEncoding() Dim byteCount As Integer = uni.GetByteCount(chars.ToCharArray(), 8, 8) bytes = New Byte(byteCount - 1) {} Dim bytesEncodedCount As Integer = uni.GetBytes(chars, 8, 8, bytes, 0) outputBlock.Text += String.Format("{0} bytes used to encode string.", bytesEncodedCount) & vbCrLf outputBlock.Text &= "Encoded bytes: " Dim b As Byte For Each b In bytes outputBlock.Text += String.Format("[{0}]", b) Next b outputBlock.Text &= vbCrLf End Sub 'Main End Class 'UnicodeEncodingExample
Note: