Convert::ToBase64CharArray Method (array<Byte>^, Int32, Int32, array<Char>^, Int32)
Converts a subset of an 8-bit unsigned integer array to an equivalent subset of a Unicode character array encoded with base-64 digits. Parameters specify the subsets as offsets in the input and output arrays, and the number of elements in the input array to convert.
Assembly: mscorlib (in mscorlib.dll)
public: static int ToBase64CharArray( array<unsigned char>^ inArray, int offsetIn, int length, array<wchar_t>^ outArray, int offsetOut )
Parameters
- inArray
-
Type:
array<System::Byte>^
An input array of 8-bit unsigned integers.
- offsetIn
-
Type:
System::Int32
A position within inArray.
- length
-
Type:
System::Int32
The number of elements of inArray to convert.
- outArray
-
Type:
array<System::Char>^
An output array of Unicode characters.
- offsetOut
-
Type:
System::Int32
A position within outArray.
| Exception | Condition |
|---|---|
| ArgumentNullException | inArray or outArray is null. |
| ArgumentOutOfRangeException | offsetIn, offsetOut, or length is negative. -or- offsetIn plus length is greater than the length of inArray. -or- offsetOut plus the number of elements to return is greater than the length of outArray. |
The subset of length elements of inArray starting at position offsetIn, are taken as a numeric value and converted to a subset of elements in outArray starting at position offsetOut. The return value indicates the number of converted elements in outArray. The subset of outArray consists of base-64 digits.
The base-64 digits in ascending order from zero are the uppercase characters "A" to "Z", the lowercase characters "a" to "z", the numerals "0" to "9", and the symbols "+" and "/". The valueless character, "=", is used for trailing padding.
The offset and length parameters are 32-bit signed numbers. The offsetIn and offsetOut parameters are zero-based array positions.
 Important |
|---|
The ToBase64CharArraymethod is designed to process a single byte array that contains all the data to be encoded. To create a base-64 character array from a byte stream, use the System.Security.Cryptography::ToBase64Transform class. |
The following example demonstrates using the ToBase64CharArray method to UUencode (encode in base 64) a binary stream, then save the encoding to a file.
public: void EncodeWithCharArray() { FileStream^ inFile; array<Byte>^binaryData; try { inFile = gcnew FileStream( inputFileName, FileMode::Open, FileAccess::Read ); binaryData = gcnew array<Byte>((int)(inFile->Length)); long bytesRead = inFile->Read( binaryData, 0, (int)inFile->Length ); inFile->Close(); } catch ( Exception^ exp ) { // Error creating stream or reading from it. Console::WriteLine( "{0}", exp->Message ); return; } // Convert the binary input into Base64 UUEncoded output. // Each 3 Byte sequence in the source data becomes a 4 Byte // sequence in the character array. long arrayLength = (long)((4.0 / 3.0) * binaryData->Length); // If array length is not divisible by 4, go up to the next // multiple of 4. if ( arrayLength % 4 != 0 ) { arrayLength += 4 - arrayLength % 4; } array<Char>^ base64CharArray = gcnew array<Char>(arrayLength); try { Convert::ToBase64CharArray( binaryData, 0, binaryData->Length, base64CharArray, 0 ); } catch ( ArgumentNullException^ ) { Console::WriteLine( "Binary data array is null." ); return; } catch ( ArgumentOutOfRangeException^ ) { Console::WriteLine( "Char Array is not large enough." ); return; } // Write the UUEncoded version to the output file. StreamWriter^ outFile; try { outFile = gcnew StreamWriter( outputFileName, false, Text::Encoding::ASCII ); outFile->Write( base64CharArray ); outFile->Close(); } catch ( Exception^ exp ) { // Error creating stream or writing to it. Console::WriteLine( " {0}", exp->Message ); } }
Available since 8
.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Silverlight
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1