GetString Method (Byte[])
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Encoding.GetString Method (Byte())

 

When overridden in a derived class, decodes all the bytes in the specified byte array into a string.

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

Public Overridable Function GetString (
	bytes As Byte()
) As String

Parameters

bytes
Type: System.Byte()

The byte array containing the sequence of bytes to decode.

Return Value

Type: System.String

A string that contains the results of decoding the specified sequence of bytes.

Exception Condition
ArgumentException

The byte array contains invalid Unicode code points.

ArgumentNullException

bytes is null.

DecoderFallbackException

A fallback occurred (see Character Encoding in the .NET Framework for complete explanation)

-and-

DecoderFallback is set to DecoderExceptionFallback.

If the data to be converted is available only in sequential blocks (such as data read from a stream) or if the amount of data is so large that it needs to be divided into smaller blocks, you should use the Decoder object returned by the GetDecoder method of a derived class.

See the Remarks section of the Encoding.GetChars reference topic for a discussion of decoding techniques and considerations.

Note that the precise behavior of the GetString method for a particular Encoding implementation depends on the fallback strategy defined for that Encoding object. For more information, see the "Choosing a Fallback Strategy" section of the Character Encoding in the .NET Framework topic.

The following example reads a UTF-8 encoded string from a binary file represented by a FileStream object. For files that are smaller than 2,048 bytes, it reads the contents of the entire file into a byte array and calls the GetString(Byte()) method to perform the decoding. For larger files, it reads 2,048 bytes at a time into a byte array, calls the Decoder.GetCharCount(Byte(), Int32, Int32) method to determine how many characters are contained in the array, and then calls the Decoder.GetChars(Byte(), Int32, Int32, Char(), Int32) method to perform the decoding.

Imports System.IO
Imports System.Text

Module Example
   Const MAX_BUFFER_SIZE As Integer = 2048

   Dim enc8 As Encoding = Encoding.UTF8

   Public Sub Main()
      Dim fStream As New FileStream(".\Utf8Example.txt", FileMode.Open)
      Dim contents As String = Nothing

      ' If file size is small, read in a single operation.
      If fStream.Length <= MAX_BUFFER_SIZE Then
         Dim bytes(CInt(fStream.Length) - 1) As Byte
         fStream.Read(bytes, 0, bytes.Length)
         contents = enc8.GetString(bytes)
      ' If file size exceeds buffer size, perform multiple reads.
      Else
         contents = ReadFromBuffer(fStream)
      End If
      fStream.Close()
      Console.WriteLine(contents)
   End Sub   

    Private Function ReadFromBuffer(fStream As FileStream) As String
        Dim bytes(MAX_BUFFER_SIZE) As Byte
        Dim output As String = String.Empty
        Dim decoder8 As Decoder = enc8.GetDecoder()

        Do While fStream.Position < fStream.Length
           Dim nBytes As Integer = fStream.Read(bytes, 0, bytes.Length)
           Dim nChars As Integer = decoder8.GetCharCount(bytes, 0, nBytes)
           Dim chars(nChars - 1) As Char
           nChars = decoder8.GetChars(bytes, 0, nBytes, chars, 0)
           output += New String(chars, 0, nChars)                                                     
        Loop
        Return output
    End Function
End Module
' The example displays the following output:
'     This is a UTF-8-encoded file that contains primarily Latin text, although it
'     does list the first twelve letters of the Russian (Cyrillic) alphabet:
'     
'     ? ? ? ? ? ? ? ? ? ? ? ?
'     
'     The goal is to save this file, then open and decode it as a binary stream.

The example uses the following text, which should be saved to a UTF-8 encoded file named Utf8Example.txt.


This is a UTF-8-encoded file that contains primarily Latin text, although it 
does list the first twelve letters of the Russian (Cyrillic) alphabet:

А б в г д е ё ж з и й к

The goal is to save this file, then open and decode it as a binary stream.

Universal Windows Platform
Available since 10
.NET Framework
Available since 1.1
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