本文整理匯總了VB.NET中System.Text.Encoding.ASCII屬性的典型用法代碼示例。如果您正苦於以下問題：VB.NET Encoding.ASCII屬性的具體用法？VB.NET Encoding.ASCII怎麽用？VB.NET Encoding.ASCII使用的例子？那麽, 這裏精選的屬性代碼示例或許可以為您提供幫助。您也可以進一步了解該屬性所在類System.Text.Encoding的用法示例。
在下文中一共展示了Encoding.ASCII屬性的3個代碼示例，這些例子默認根據受歡迎程度排序。您可以為喜歡或者感覺有用的代碼點讚，您的評價將有助於係統推薦出更棒的VB.NET代碼示例。
示例1: EncodingExample
' 導入命名空間
Imports System.Text
Class EncodingExample
Public Shared Sub Main()
' Create and ASCII encoding.
Dim ascii As Encoding = Encoding.ASCII
' A Unicode string with two characters outside the ASCII code range.
Dim unicodeString As String = "This unicode string contains two characters " + "with codes outside the ASCII code range, " + "Pi (" & ChrW(&H03A0) & ") and Sigma (" & ChrW(&H03A3) & ")."
Console.WriteLine("Original string:")
Console.WriteLine(unicodeString)
' Save the positions of the special characters for later reference.
Dim indexOfPi As Integer = unicodeString.IndexOf(ChrW(&H03A0))
Dim indexOfSigma As Integer = unicodeString.IndexOf(ChrW(&H03A3))
' Encode the string.
Dim encodedBytes As Byte() = ascii.GetBytes(unicodeString)
Console.WriteLine()
Console.WriteLine("Encoded bytes:")
For Each b In encodedBytes
Console.Write("[{0}]", b)
Next b
Console.WriteLine()
' Notice that the special characters have been replaced with
' the value 63, which is the ASCII character code for '?'.
Console.WriteLine()
Console.WriteLine("Value at position of Pi character: {0}", encodedBytes(indexOfPi))
Console.WriteLine("Value at position of Sigma character: {0}", encodedBytes(indexOfSigma))
' Decode bytes back to a string.
' Notice missing Pi and Sigma characters.
Dim decodedString As String = ascii.GetString(encodedBytes)
Console.WriteLine()
Console.WriteLine("Decoded bytes:")
Console.WriteLine(decodedString)
End Sub
End Class輸出：
Original string: This unicode string contains two characters with codes outside 'the ASCII code range, Pi (ã) and Sigma (ä). Encoded bytes: [84][104][105][115][32][117][110][105][99][111][100][101][32]'[115][116][114][105][110][103][32][99][111][110][116][97]'[105][110][115][32][116][119][111][32][99][104][97][114][97]'[99][116][101][114][115][32][119][105][116][104][32][99][111]'[100][101][115][32][111][117][116][115][105][100][101][32]'[116][104][101][32][65][83][67][73][73][32][99][111][100]'[101][32][114][97][110][103][101][44][32][80][105][32][40]'[63][41][32][97][110][100][32][83][105][103][109][97][32][40]'[63][41][46] Value at position of Pi character: 63 Value at position of Sigma character: 63 Decoded bytes: This unicode string contains two characters with codes outside 'the ASCII code range, Pi (?) and Sigma (?).
示例2: Main
' 導入命名空間
Imports System.Text
Module Example
Public Sub Main()
Dim enc As Encoding = Encoding.GetEncoding("us-ascii",
New EncoderExceptionFallback(),
New DecoderExceptionFallback())
Dim value As String = String.Format("{0} {1} {2}",
ChrW(&h00C4), ChrW(&h00F6), ChrW(&h00AE))
Try
Dim bytes() As Byte = enc.GetBytes(value)
For Each byt As Byte In bytes
Console.Write("{0:X2} ", byt)
Next
Console.WriteLine()
Dim value2 As String = enc.GetString(bytes)
Console.WriteLine(value2)
Catch e As EncoderFallbackException
Console.WriteLine("Unable to encode {0} at index {1}",
If(e.IsUnknownSurrogate(),
String.Format("U+{0:X4} U+{1:X4}",
Convert.ToUInt16(e.CharUnknownHigh),
Convert.ToUInt16(e.CharUnknownLow)),
String.Format("U+{0:X4}",
Convert.ToUInt16(e.CharUnknown))),
e.Index)
End Try
End Sub
End Module輸出：
Unable to encode U+00C4 at index 0
示例3: MainClass
' 導入命名空間
Imports System
Imports System.IO
Imports System.Security.Cryptography
Imports System.Text
Imports System.Runtime.Serialization.Formatters
public class MainClass
Shared Public Sub Main(ByVal CmdArgs() As String)
If (CmdArgs.Length <> 1) Then
Console.WriteLine("usage: TestKeyHash <filename>")
End
End If
Dim key() As Byte = Encoding.ASCII.GetBytes("My Secret Key".ToCharArray())
Dim hmac As HMACSHA1 = New HMACSHA1(key)
Dim fs As FileStream = File.OpenRead(CmdArgs(0))
Dim hash() As Byte = hmac.ComputeHash(fs)
Dim b64 As String = Convert.ToBase64String(hash)
fs.Close()
Console.WriteLine(b64)
End Sub
End Class