Convert.FromBase64CharArray(Char[], Int32, Int32) 方法

参考

定义

命名空间:: System

程序集:: System.Runtime.Extensions.dll

程序集:: System.Runtime.dll

程序集:: mscorlib.dll

程序集:: netstandard.dll

重要

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将 Unicode 字符数组（它将二进制数据编码为 Base64 数字）的子集转换为等效的 8 位无符号整数数组。参数指定输入数组的子集以及要转换的元素数。

public:
 static cli::array <System::Byte> ^ FromBase64CharArray(cli::array <char> ^ inArray, int offset, int length);

public static byte[] FromBase64CharArray (char[] inArray, int offset, int length);

static member FromBase64CharArray : char[] * int * int -> byte[]

Public Shared Function FromBase64CharArray (inArray As Char(), offset As Integer, length As Integer) As Byte()

参数

inArray: Char[]

Unicode 字符数组。

offset: Int32

inArray 中的位置。

length: Int32

inArray 中要转换的元素数目。

Byte[]

等效于 length 中位于 offset 位置的 inArray 元素的 8 位无符号整数数组。

例外

ArgumentNullException

inArray 上声明的默认值为 null。

ArgumentOutOfRangeException

offset 或 length 小于 0。

或 -

offset 加 length 表示不在 inArray 内的位置。

FormatException

inArray 的长度（忽略空格）不是 0 或 4 的倍数。

或 -

inArray 的格式无效。 inArray 包含非 base 64 字符、两个以上的填充字符或者在填充字符中包含非空格字符。

示例

以下示例演示如何使用 FromBase64CharArray(Char[], Int32, Int32) 该方法解码 UUencoded (base-64) 数据并将其另存为二进制输出。

public:
   void DecodeWithCharArray()
   {
      StreamReader^ inFile;
      array<Char>^base64CharArray;
      try
      {
         inFile = gcnew StreamReader( inputFileName,
                                      Text::Encoding::ASCII );
         base64CharArray = gcnew array<Char>((int)(inFile->BaseStream->Length));
         inFile->Read( base64CharArray, 0, (int)inFile->BaseStream->Length );
         inFile->Close();
      }
      catch ( Exception^ exp ) 
      {
         
         // Error creating stream or reading from it.
         Console::WriteLine( "{0}", exp->Message );
         return;
      }
      
      // Convert the Base64 UUEncoded input into binary output.
      array<Byte>^binaryData;
      try
      {
         binaryData = Convert::FromBase64CharArray( base64CharArray,
                                                    0,
                                                    base64CharArray->Length );
      }
      catch ( ArgumentNullException^ ) 
      {
         Console::WriteLine( "Base 64 character array is null." );
         return;
      }
      catch ( FormatException^ ) 
      {
         Console::WriteLine( "Base 64 Char Array length is not " +
            "4 or is not an even multiple of 4." );
         return;
      }
      
      // Write out the decoded data.
      FileStream^ outFile;
      try
      {
         outFile = gcnew FileStream( outputFileName,
                                     FileMode::Create,
                                     FileAccess::Write );
         outFile->Write( binaryData, 0, binaryData->Length );
         outFile->Close();
      }
      catch ( Exception^ exp ) 
      {
         // Error creating stream or writing to it.
         Console::WriteLine( "{0}", exp->Message );
      }
   }

public void DecodeWithCharArray() {
   System.IO.StreamReader inFile;
   char[] base64CharArray;

   try {
      inFile = new System.IO.StreamReader(inputFileName,
                              System.Text.Encoding.ASCII);
      base64CharArray = new char[inFile.BaseStream.Length];
      inFile.Read(base64CharArray, 0, (int)inFile.BaseStream.Length);
      inFile.Close();
   }
   catch (System.Exception exp) {
      // Error creating stream or reading from it.
      System.Console.WriteLine("{0}", exp.Message);
      return;
   }

   // Convert the Base64 UUEncoded input into binary output.
   byte[] binaryData;
   try {
      binaryData =
         System.Convert.FromBase64CharArray(base64CharArray,
                                    0,
                                    base64CharArray.Length);
   }
   catch ( System.ArgumentNullException ) {
      System.Console.WriteLine("Base 64 character array is null.");
      return;
   }
   catch ( System.FormatException ) {
      System.Console.WriteLine("Base 64 Char Array length is not " +
         "4 or is not an even multiple of 4." );
      return;
   }

   // Write out the decoded data.
   System.IO.FileStream outFile;
   try {
      outFile = new System.IO.FileStream(outputFileName,
                                 System.IO.FileMode.Create,
                                 System.IO.FileAccess.Write);
      outFile.Write(binaryData, 0, binaryData.Length);
      outFile.Close();
   }
   catch (System.Exception exp) {
      // Error creating stream or writing to it.
      System.Console.WriteLine("{0}", exp.Message);
   }
}

let decodeWithCharArray () =
    try
        let inFile =
            new StreamReader(inputFileName, Encoding.ASCII)

        let base64CharArray =
            Array.zeroCreate<char> (int inFile.BaseStream.Length)

        inFile.Read(base64CharArray, 0, (int) inFile.BaseStream.Length)
        |> ignore

        // Convert the Base64 UUEncoded input into binary output.
        let binaryData =
            Convert.FromBase64CharArray(base64CharArray, 0, base64CharArray.Length)
        // Write out the decoded data.
        use outFile =
            new FileStream(outputFileName, FileMode.Create, FileAccess.Write)

        outFile.Write(binaryData, 0, binaryData.Length)
    with
    | :? ArgumentNullException -> printfn "Base 64 character array is null."
    | :? FormatException -> printfn "Base 64 Char Array length is not 4 or is not an even multiple of 4."
    | e -> printfn $"{e.Message}"

Public Sub DecodeWithCharArray()
   Dim inFile As System.IO.StreamReader
   Dim base64CharArray() As Char

   Try
      inFile = New System.IO.StreamReader(inputFileName, _
                                          System.Text.Encoding.ASCII)

      ReDim base64CharArray(inFile.BaseStream.Length - 1)
      inFile.Read(base64CharArray, 0, inFile.BaseStream.Length)
      inFile.Close()
   Catch exp As System.Exception
      ' Error creating stream or reading from it.
      System.Console.WriteLine("{0}", exp.Message)
      Return
   End Try

   ' Convert the Base64 UUEncoded input into binary output.
   Dim binaryData() As Byte
   Try
      binaryData = System.Convert.FromBase64CharArray(base64CharArray, 0, _
                                                base64CharArray.Length)
   Catch exp As System.ArgumentNullException
      System.Console.WriteLine("Base 64 character array is null.")
      Return
   Catch exp As System.FormatException
      System.Console.WriteLine("Base 64 Char Array length is not " + _
               "4 or is not an even multiple of 4")
      Return
   End Try

   ' Write out the decoded data.
   Dim outFile As System.IO.FileStream
   Try
      outFile = New System.IO.FileStream(outputFileName, _
                                         System.IO.FileMode.Create, _
                                         System.IO.FileAccess.Write)
      outFile.Write(binaryData, 0, binaryData.Length - 1)
      outFile.Close()
   Catch exp As System.Exception
      ' Error creating stream or writing to it.
      System.Console.WriteLine("{0}", exp.Message)
   End Try
End Sub

下面的示例演示 ToBase64CharArray(Byte[], Int32, Int32, Char[], Int32, Base64FormattingOptions) 了和 FromBase64CharArray(Char[], Int32, Int32) 方法。输入分为三个字节组， (每个字节) 24 位。因此，每个组由四个 6 位数字组成，其中每个数字范围为十进制 0 到 63。在此示例中，有 85 个 3 字节组，其余一个字节。第一组由十六进制值 00、01 和 02 组成，后者生成四个 6 位值等于十进制 0、0、4 和 2。这四个值对应于输出开头的 base-64 数字“A”、“A”、“E”和“C”。

如果 3 字节组的整型数不存在，则剩余的字节有效填充为零，形成完整的组。在此示例中，最后一个字节的值是十六进制 FF。前 6 位等于十进制 63，对应于输出末尾的 base-64 位“/”，接下来的 2 位填充为零，以生成十进制 48，对应于 base-64 数字“w”。最后两个 6 位值是填充值，对应于无值填充字符“=”。

// This example demonstrates the Convert.ToBase64CharArray() and
//                               Convert.FromBase64CharArray methods
using namespace System;
bool ArraysAreEqual( array<Byte>^a1, array<Byte>^a2 );
int main()
{
   array<Byte>^byteArray1 = gcnew array<Byte>(256);
   array<Byte>^byteArray2 = gcnew array<Byte>(256);
   array<Char>^charArray = gcnew array<Char>(352);
   int charArrayLength;
   String^ nl = Environment::NewLine;
   String^ ruler1a = "         1         2         3         4";
   String^ ruler2a = "1234567890123456789012345678901234567890";
   String^ ruler3a = "----+----+----+----+----+----+----+----+";
   String^ ruler1b = "         5         6         7      ";
   String^ ruler2b = "123456789012345678901234567890123456";
   String^ ruler3b = "----+----+----+----+----+----+----+-";
   String^ ruler = String::Concat( ruler1a, ruler1b, nl, ruler2a, ruler2b, nl, ruler3a, ruler3b );
   
   // 1) Initialize and display a Byte array of arbitrary data.
   Console::WriteLine( "1) Input: A Byte array of arbitrary data.{0}", nl );
   for ( int x = 0; x < byteArray1->Length; x++ )
   {
      byteArray1[ x ] = (Byte)x;
      Console::Write( "{0:X2} ", byteArray1[ x ] );
      if ( ((x + 1) % 20) == 0 )
            Console::WriteLine();

   }
   Console::Write( "{0}{0}", nl );
   
   // 2) Convert the input Byte array to a Char array, with newlines inserted.
   charArrayLength = Convert::ToBase64CharArray( byteArray1, 0, byteArray1->Length, 
                                                 charArray, 0, 
                                                 Base64FormattingOptions::InsertLineBreaks );
   Console::WriteLine( "2) Convert the input Byte array to a Char array with newlines." );
   Console::Write( "   Output: A Char array (length = {0}). ", charArrayLength );
   Console::WriteLine( "The elements of the array are:{0}", nl );
   Console::WriteLine( ruler );
   Console::WriteLine( gcnew String( charArray ) );
   Console::WriteLine();
   
   // 3) Convert the Char array back to a Byte array.
   Console::WriteLine( "3) Convert the Char array to an output Byte array." );
   byteArray2 = Convert::FromBase64CharArray( charArray, 0, charArrayLength );
   
   // 4) Are the input and output Byte arrays equivalent?
   Console::WriteLine( "4) The output Byte array is equal to the input Byte array: {0}", ArraysAreEqual( byteArray1, byteArray2 ) );
}

bool ArraysAreEqual( array<Byte>^a1, array<Byte>^a2 )
{
   if ( a1->Length != a2->Length )
      return false;

   for ( int i = 0; i < a1->Length; i++ )
      if ( a1[ i ] != a2[ i ] )
            return false;

   return true;
}

/*
This example produces the following results:

1) Input: A Byte array of arbitrary data.

00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 10 11 12 13
14 15 16 17 18 19 1A 1B 1C 1D 1E 1F 20 21 22 23 24 25 26 27
28 29 2A 2B 2C 2D 2E 2F 30 31 32 33 34 35 36 37 38 39 3A 3B
3C 3D 3E 3F 40 41 42 43 44 45 46 47 48 49 4A 4B 4C 4D 4E 4F
50 51 52 53 54 55 56 57 58 59 5A 5B 5C 5D 5E 5F 60 61 62 63
64 65 66 67 68 69 6A 6B 6C 6D 6E 6F 70 71 72 73 74 75 76 77
78 79 7A 7B 7C 7D 7E 7F 80 81 82 83 84 85 86 87 88 89 8A 8B
8C 8D 8E 8F 90 91 92 93 94 95 96 97 98 99 9A 9B 9C 9D 9E 9F
A0 A1 A2 A3 A4 A5 A6 A7 A8 A9 AA AB AC AD AE AF B0 B1 B2 B3
B4 B5 B6 B7 B8 B9 BA BB BC BD BE BF C0 C1 C2 C3 C4 C5 C6 C7
C8 C9 CA CB CC CD CE CF D0 D1 D2 D3 D4 D5 D6 D7 D8 D9 DA DB
DC DD DE DF E0 E1 E2 E3 E4 E5 E6 E7 E8 E9 EA EB EC ED EE EF
F0 F1 F2 F3 F4 F5 F6 F7 F8 F9 FA FB FC FD FE FF

2) Convert the input Byte array to a Char array with newlines.
   Output: A Char array (length = 352). The elements of the array are:

         1         2         3         4         5         6         7
1234567890123456789012345678901234567890123456789012345678901234567890123456
----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+-
AAECAwQFBgcICQoLDA0ODxAREhMUFRYXGBkaGxwdHh8gISIjJCUmJygpKissLS4vMDEyMzQ1Njc4
OTo7PD0+P0BBQkNERUZHSElKS0xNTk9QUVJTVFVWV1hZWltcXV5fYGFiY2RlZmdoaWprbG1ub3Bx
cnN0dXZ3eHl6e3x9fn+AgYKDhIWGh4iJiouMjY6PkJGSk5SVlpeYmZqbnJ2en6ChoqOkpaanqKmq
q6ytrq+wsbKztLW2t7i5uru8vb6/wMHCw8TFxsfIycrLzM3Oz9DR0tPU1dbX2Nna29zd3t/g4eLj
5OXm5+jp6uvs7e7v8PHy8/T19vf4+fr7/P3+/w==

3) Convert the Char array to an output Byte array.
4) The output Byte array is equal to the input Byte array: True

*/

// This example demonstrates the Convert.ToBase64CharArray() and
//                               Convert.FromBase64CharArray methods

using System;

class Sample
{
    public static void Main()
    {
    byte[] byteArray1 = new byte[256];
    byte[] byteArray2 = new byte[256];
    char[] charArray  = new char[352];
    int charArrayLength;
    string nl = Environment.NewLine;

    string ruler1a = "         1         2         3         4";
    string ruler2a = "1234567890123456789012345678901234567890";
    string ruler3a = "----+----+----+----+----+----+----+----+";
    string ruler1b = "         5         6         7      ";
    string ruler2b = "123456789012345678901234567890123456";
    string ruler3b = "----+----+----+----+----+----+----+-";
    string ruler   = String.Concat(ruler1a, ruler1b, nl,
                                   ruler2a, ruler2b, nl,
                                   ruler3a, ruler3b);

// 1) Initialize and display a Byte array of arbitrary data.
    Console.WriteLine("1) Input: A Byte array of arbitrary data.{0}", nl);
    for (int x = 0; x < byteArray1.Length; x++)
    {
    byteArray1[x] = (byte)x;
    Console.Write("{0:X2} ", byteArray1[x]);
    if (((x+1)%20) == 0) Console.WriteLine();
    }
    Console.Write("{0}{0}", nl);

// 2) Convert the input Byte array to a Char array, with newlines inserted.
    charArrayLength =
        Convert.ToBase64CharArray(byteArray1, 0, byteArray1.Length,
                                   charArray, 0, Base64FormattingOptions.InsertLineBreaks);
    Console.WriteLine("2) Convert the input Byte array to a Char array with newlines.");
    Console.Write("   Output: A Char array (length = {0}). ", charArrayLength);
    Console.WriteLine("The elements of the array are:{0}", nl);
    Console.WriteLine(ruler);
    Console.WriteLine(new String(charArray));
    Console.WriteLine();

// 3) Convert the Char array back to a Byte array.
    Console.WriteLine("3) Convert the Char array to an output Byte array.");
    byteArray2 = Convert.FromBase64CharArray(charArray, 0, charArrayLength);

// 4) Are the input and output Byte arrays equivalent?
    Console.WriteLine("4) The output Byte array is equal to the input Byte array: {0}",
                      ArraysAreEqual(byteArray1, byteArray2));
    }

    public static bool ArraysAreEqual(byte[] a1, byte[] a2)
    {
    if (a1.Length != a2.Length) return false;
    for (int i = 0; i < a1.Length; i++)
        if (a1[i] != a2[i]) return false;
    return true;
    }
}
/*
This example produces the following results:

1) Input: A Byte array of arbitrary data.

00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 10 11 12 13
14 15 16 17 18 19 1A 1B 1C 1D 1E 1F 20 21 22 23 24 25 26 27
28 29 2A 2B 2C 2D 2E 2F 30 31 32 33 34 35 36 37 38 39 3A 3B
3C 3D 3E 3F 40 41 42 43 44 45 46 47 48 49 4A 4B 4C 4D 4E 4F
50 51 52 53 54 55 56 57 58 59 5A 5B 5C 5D 5E 5F 60 61 62 63
64 65 66 67 68 69 6A 6B 6C 6D 6E 6F 70 71 72 73 74 75 76 77
78 79 7A 7B 7C 7D 7E 7F 80 81 82 83 84 85 86 87 88 89 8A 8B
8C 8D 8E 8F 90 91 92 93 94 95 96 97 98 99 9A 9B 9C 9D 9E 9F
A0 A1 A2 A3 A4 A5 A6 A7 A8 A9 AA AB AC AD AE AF B0 B1 B2 B3
B4 B5 B6 B7 B8 B9 BA BB BC BD BE BF C0 C1 C2 C3 C4 C5 C6 C7
C8 C9 CA CB CC CD CE CF D0 D1 D2 D3 D4 D5 D6 D7 D8 D9 DA DB
DC DD DE DF E0 E1 E2 E3 E4 E5 E6 E7 E8 E9 EA EB EC ED EE EF
F0 F1 F2 F3 F4 F5 F6 F7 F8 F9 FA FB FC FD FE FF

2) Convert the input Byte array to a Char array with newlines.
   Output: A Char array (length = 352). The elements of the array are:

         1         2         3         4         5         6         7
1234567890123456789012345678901234567890123456789012345678901234567890123456
----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+-
AAECAwQFBgcICQoLDA0ODxAREhMUFRYXGBkaGxwdHh8gISIjJCUmJygpKissLS4vMDEyMzQ1Njc4
OTo7PD0+P0BBQkNERUZHSElKS0xNTk9QUVJTVFVWV1hZWltcXV5fYGFiY2RlZmdoaWprbG1ub3Bx
cnN0dXZ3eHl6e3x9fn+AgYKDhIWGh4iJiouMjY6PkJGSk5SVlpeYmZqbnJ2en6ChoqOkpaanqKmq
q6ytrq+wsbKztLW2t7i5uru8vb6/wMHCw8TFxsfIycrLzM3Oz9DR0tPU1dbX2Nna29zd3t/g4eLj
5OXm5+jp6uvs7e7v8PHy8/T19vf4+fr7/P3+/w==

3) Convert the Char array to an output Byte array.
4) The output Byte array is equal to the input Byte array: True

*/

// This example demonstrates the Convert.ToBase64CharArray() and
//                               Convert.FromBase64CharArray methods
open System

let arraysAreEqual (a1: byte[]) (a2: byte[]) =
    a1.Length = a2.Length &&
    Array.forall2 (=) a2 a1

let byteArray1 = Array.zeroCreate<byte> 256
let charArray  = Array.zeroCreate<char> 352
let nl = Environment.NewLine

let ruler =
    $"         1         2         3         4         5         6         7      {nl}" +
    $"1234567890123456789012345678901234567890123456789012345678901234567890123456{nl}" +
    "----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+-"

// 1) Initialize and display a Byte array of arbitrary data.
printfn $"1) Input: A Byte array of arbitrary data.{nl}"
for i = 0 to byteArray1.Length - 1 do
    byteArray1[i] <- byte i
    printf $"{byteArray1[i]:X2} "
    if (i + 1) % 20 = 0 then 
        printfn ""
printf $"{nl}{nl}"

// 2) Convert the input Byte array to a Char array, with newlines inserted.
let charArrayLength =
    Convert.ToBase64CharArray(byteArray1, 0, byteArray1.Length,
                              charArray, 0, Base64FormattingOptions.InsertLineBreaks)
printfn "2) Convert the input Byte array to a Char array with newlines."
printf $"   Output: A Char array (length = {charArrayLength}). "
printfn $"The elements of the array are:{nl}"
printfn $"{ruler}"
printfn $"{String charArray}"
printfn ""

// 3) Convert the Char array back to a Byte array.
printfn "3) Convert the Char array to an output Byte array."
let byteArray2 = Convert.FromBase64CharArray(charArray, 0, charArrayLength)

// 4) Are the input and output Byte arrays equivalent?
printfn $"4) The output Byte array is equal to the input Byte array: {arraysAreEqual byteArray1 byteArray2}"


// This example produces the following results:
//     1) Input: A Byte array of arbitrary data.
//    
//     00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 10 11 12 13
//     14 15 16 17 18 19 1A 1B 1C 1D 1E 1F 20 21 22 23 24 25 26 27
//     28 29 2A 2B 2C 2D 2E 2F 30 31 32 33 34 35 36 37 38 39 3A 3B
//     3C 3D 3E 3F 40 41 42 43 44 45 46 47 48 49 4A 4B 4C 4D 4E 4F
//     50 51 52 53 54 55 56 57 58 59 5A 5B 5C 5D 5E 5F 60 61 62 63
//     64 65 66 67 68 69 6A 6B 6C 6D 6E 6F 70 71 72 73 74 75 76 77
//     78 79 7A 7B 7C 7D 7E 7F 80 81 82 83 84 85 86 87 88 89 8A 8B
//     8C 8D 8E 8F 90 91 92 93 94 95 96 97 98 99 9A 9B 9C 9D 9E 9F
//     A0 A1 A2 A3 A4 A5 A6 A7 A8 A9 AA AB AC AD AE AF B0 B1 B2 B3
//     B4 B5 B6 B7 B8 B9 BA BB BC BD BE BF C0 C1 C2 C3 C4 C5 C6 C7
//     C8 C9 CA CB CC CD CE CF D0 D1 D2 D3 D4 D5 D6 D7 D8 D9 DA DB
//     DC DD DE DF E0 E1 E2 E3 E4 E5 E6 E7 E8 E9 EA EB EC ED EE EF
//     F0 F1 F2 F3 F4 F5 F6 F7 F8 F9 FA FB FC FD FE FF
//    
//     2) Convert the input Byte array to a Char array with newlines.
//        Output: A Char array (length = 352). The elements of the array are:
//    
//              1         2         3         4         5         6         7
//     1234567890123456789012345678901234567890123456789012345678901234567890123456
//     ----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+-
//     AAECAwQFBgcICQoLDA0ODxAREhMUFRYXGBkaGxwdHh8gISIjJCUmJygpKissLS4vMDEyMzQ1Njc4
//     OTo7PD0+P0BBQkNERUZHSElKS0xNTk9QUVJTVFVWV1hZWltcXV5fYGFiY2RlZmdoaWprbG1ub3Bx
//     cnN0dXZ3eHl6e3x9fn+AgYKDhIWGh4iJiouMjY6PkJGSk5SVlpeYmZqbnJ2en6ChoqOkpaanqKmq
//     q6ytrq+wsbKztLW2t7i5uru8vb6/wMHCw8TFxsfIycrLzM3Oz9DR0tPU1dbX2Nna29zd3t/g4eLj
//     5OXm5+jp6uvs7e7v8PHy8/T19vf4+fr7/P3+/w==
//    
//     3) Convert the Char array to an output Byte array.
//     4) The output Byte array is equal to the input Byte array: True

' This example demonstrates the Convert.ToBase64CharArray() and 
'                               Convert.FromBase64CharArray methods
Class Sample
   Public Shared Sub Main()
      Dim byteArray1(255) As Byte
      Dim byteArray2(255) As Byte
      Dim charArray(351) As Char
      Dim charArrayLength As Integer
      Dim nl As String = Environment.NewLine
      
      Dim ruler1a As String = "         1         2         3         4"
      Dim ruler2a As String = "1234567890123456789012345678901234567890"
      Dim ruler3a As String = "----+----+----+----+----+----+----+----+"
      Dim ruler1b As String = "         5         6         7      "
      Dim ruler2b As String = "123456789012345678901234567890123456"
      Dim ruler3b As String = "----+----+----+----+----+----+----+-"
      Dim ruler As String = String.Concat(ruler1a, ruler1b, nl, _
                                          ruler2a, ruler2b, nl, _
                                          ruler3a, ruler3b)

      ' 1) Initialize and display a Byte array of arbitrary data.
      Console.WriteLine("1) Input: A Byte array of arbitrary data.{0}", nl)
      Dim x As Integer
      For x = 0 To byteArray1.Length - 1
         byteArray1(x) = CByte(x)
         Console.Write("{0:X2} ", byteArray1(x))
         If(x + 1) Mod 20 = 0 Then
            Console.WriteLine()
         End If
      Next x
      Console.Write("{0}{0}", nl)
      
      ' 2) Convert the input Byte array to a Char array, with newlines inserted.
      charArrayLength = Convert.ToBase64CharArray( _
                                byteArray1, 0, byteArray1.Length, _
                                charArray, 0, _
                                Base64FormattingOptions.InsertLineBreaks)
      Console.WriteLine("2) Convert the input Byte array to a Char array with newlines.")
      Console.Write("   Output: A Char array (length = {0}). ", charArrayLength)
      Console.WriteLine("The elements of the array are:{0}", nl)
      Console.WriteLine(ruler)
      Console.WriteLine(New [String](charArray))
      Console.WriteLine()
      
      ' 3) Convert the Char array back to a Byte array.
      Console.WriteLine("3) Convert the Char array to an output Byte array.")
      byteArray2 = Convert.FromBase64CharArray(charArray, 0, charArrayLength)
      
      ' 4) Are the input and output Byte arrays equivalent?
      Console.WriteLine("4) The output Byte array is equal to the input Byte array: {0}", _
                            ArraysAreEqual(byteArray1, byteArray2))
   End Sub
   
   Public Shared Function ArraysAreEqual(a1() As Byte, a2() As Byte) As Boolean
      If a1.Length <> a2.Length Then
         Return False
      End If
      Dim i As Integer
      For i = 0 To a1.Length - 1
         If a1(i) <> a2(i) Then
            Return False
         End If
      Next i
      Return True
   End Function 'ArraysAreEqual
End Class
'
'This example produces the following results:
'
'1) Input: A Byte array of arbitrary data.
'
'00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 10 11 12 13
'14 15 16 17 18 19 1A 1B 1C 1D 1E 1F 20 21 22 23 24 25 26 27
'28 29 2A 2B 2C 2D 2E 2F 30 31 32 33 34 35 36 37 38 39 3A 3B
'3C 3D 3E 3F 40 41 42 43 44 45 46 47 48 49 4A 4B 4C 4D 4E 4F
'50 51 52 53 54 55 56 57 58 59 5A 5B 5C 5D 5E 5F 60 61 62 63
'64 65 66 67 68 69 6A 6B 6C 6D 6E 6F 70 71 72 73 74 75 76 77
'78 79 7A 7B 7C 7D 7E 7F 80 81 82 83 84 85 86 87 88 89 8A 8B
'8C 8D 8E 8F 90 91 92 93 94 95 96 97 98 99 9A 9B 9C 9D 9E 9F
'A0 A1 A2 A3 A4 A5 A6 A7 A8 A9 AA AB AC AD AE AF B0 B1 B2 B3
'B4 B5 B6 B7 B8 B9 BA BB BC BD BE BF C0 C1 C2 C3 C4 C5 C6 C7
'C8 C9 CA CB CC CD CE CF D0 D1 D2 D3 D4 D5 D6 D7 D8 D9 DA DB
'DC DD DE DF E0 E1 E2 E3 E4 E5 E6 E7 E8 E9 EA EB EC ED EE EF
'F0 F1 F2 F3 F4 F5 F6 F7 F8 F9 FA FB FC FD FE FF
'
'2) Convert the input Byte array to a Char array with newlines.
'   Output: A Char array (length = 352). The elements of the array are:
'
'         1         2         3         4         5         6         7
'1234567890123456789012345678901234567890123456789012345678901234567890123456
'----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+-
'AAECAwQFBgcICQoLDA0ODxAREhMUFRYXGBkaGxwdHh8gISIjJCUmJygpKissLS4vMDEyMzQ1Njc4
'OTo7PD0+P0BBQkNERUZHSElKS0xNTk9QUVJTVFVWV1hZWltcXV5fYGFiY2RlZmdoaWprbG1ub3Bx
'cnN0dXZ3eHl6e3x9fn+AgYKDhIWGh4iJiouMjY6PkJGSk5SVlpeYmZqbnJ2en6ChoqOkpaanqKmq
'q6ytrq+wsbKztLW2t7i5uru8vb6/wMHCw8TFxsfIycrLzM3Oz9DR0tPU1dbX2Nna29zd3t/g4eLj
'5OXm5+jp6uvs7e7v8PHy8/T19vf4+fr7/P3+/w==
'
'3) Convert the Char array to an output Byte array.
'4) The output Byte array is equal to the input Byte array: True

注解

inArray 由 base-64 数字、空格字符和尾随填充字符组成。从零开始的基数 64 位数字是大写字符“A”到“Z”，小写字符“a”到“z”，数字“0”到“9”，符号“+”和“/”。

空格字符及其 Unicode 名称和十六进制代码位是制表符 (字符制表符、U+0009) 、换行符 (行源、U+000A) 、回车 (回车、U+000D) 和空白 (空格、U+0020) 。任意数量的空白字符可以出现在其中 inArray ，因为所有空白字符将被忽略。

无值字符“=”用于尾随填充。结尾 inArray 可以包含零个、一个或两个填充字符。

重要

该方法 FromBase64CharArray 旨在处理包含要解码的所有数据的单个字符数组。若要从流解码 base-64 字符数据，请使用 System.Security.Cryptography.FromBase64Transform 该类。

适用于

通过

Convert.FromBase64CharArray(Char[], Int32, Int32) 方法

定义

参数

返回

例外

示例

注解

适用于

另请参阅

其他资源