UTF7Encoding.GetDecoder 方法
定義
重要
部分資訊涉及發行前產品,在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊,不做任何明確或隱含的瑕疵擔保。
取得可以將以 UTF-7 編碼的位元組序列轉換成 Unicode 字元序列的解碼器。
public:
override System::Text::Decoder ^ GetDecoder();
public override System.Text.Decoder GetDecoder ();
override this.GetDecoder : unit -> System.Text.Decoder
Public Overrides Function GetDecoder () As Decoder
傳回
Decoder,可以將以 UTF-7 編碼的位元組序列轉換成 Unicode 字元序列。
範例
下列程式碼範例示範如何使用 GetDecoder 方法來取得解碼器,將 UTF-7 編碼的位元組轉換成字元序列。
using namespace System;
using namespace System::Text;
using namespace System::Collections;
int main()
{
array<Char>^chars;
array<Byte>^bytes = {99,43,65,119,67,103,111,65,45};
Decoder^ utf7Decoder = Encoding::UTF7->GetDecoder();
int charCount = utf7Decoder->GetCharCount( bytes, 0, bytes->Length );
chars = gcnew array<Char>(charCount);
int charsDecodedCount = utf7Decoder->GetChars( bytes, 0, bytes->Length, chars, 0 );
Console::WriteLine( "{0} characters used to decode bytes.", charsDecodedCount );
Console::Write( "Decoded chars: " );
IEnumerator^ myEnum = chars->GetEnumerator();
while ( myEnum->MoveNext() )
{
Char c = safe_cast<Char>(myEnum->Current);
Console::Write( "[{0}]", c.ToString() );
}
Console::WriteLine();
}
using System;
using System.Text;
class UTF7EncodingExample {
public static void Main() {
Char[] chars;
Byte[] bytes = new Byte[] {
99, 43, 65, 119, 67, 103, 111, 65, 45
};
Decoder utf7Decoder = Encoding.UTF7.GetDecoder();
int charCount = utf7Decoder.GetCharCount(bytes, 0, bytes.Length);
chars = new Char[charCount];
int charsDecodedCount = utf7Decoder.GetChars(bytes, 0, bytes.Length, chars, 0);
Console.WriteLine(
"{0} characters used to decode bytes.", charsDecodedCount
);
Console.Write("Decoded chars: ");
foreach (Char c in chars) {
Console.Write("[{0}]", c);
}
Console.WriteLine();
}
}
Imports System.Text
Class UTF7EncodingExample
Public Shared Sub Main()
Dim chars() As Char
Dim bytes() As Byte = {99, 43, 65, 119, 67, 103, 111, 65, 45}
Dim utf7Decoder As Decoder = Encoding.UTF7.GetDecoder()
Dim charCount As Integer = utf7Decoder.GetCharCount(bytes, 0, bytes.Length)
chars = New Char(charCount - 1) {}
Dim charsDecodedCount As Integer = utf7Decoder.GetChars(bytes, 0, bytes.Length, chars, 0)
Console.WriteLine("{0} characters used to decode bytes.", charsDecodedCount)
Console.Write("Decoded chars: ")
Dim c As Char
For Each c In chars
Console.Write("[{0}]", c)
Next c
Console.WriteLine()
End Sub
End Class
備註
方法 Decoder.GetChars 會以類似 GetChars 這個類別的 方法,將位元組的循序區塊轉換成字元的循序區塊。 不過,會 Decoder 維護 呼叫之間的狀態資訊,以便正確地解碼跨越區塊的位元組序列。 Decoder也會在資料區塊結尾保留尾端的位元組,並在下一個解碼作業中使用尾端位元組。 因此, GetDecoder 和 GetEncoder 對於網路傳輸和檔案作業很有用,因為這些作業通常會處理資料區塊,而不是完整的資料流程。