UTF8Encoding::GetCharCount Method (array<Byte>^, Int32, Int32)
Calculates the number of characters produced by decoding a sequence of bytes from the specified byte array.
Assembly: mscorlib (in mscorlib.dll)
public: virtual int GetCharCount( array<unsigned char>^ bytes, int index, int count ) override
Parameters
- bytes
-
Type:
array<System::Byte>^
The byte array containing the sequence of bytes to decode.
- index
-
Type:
System::Int32
The index of the first byte to decode.
- count
-
Type:
System::Int32
The number of bytes to decode.
Return Value
Type: System::Int32The number of characters produced by decoding the specified sequence of bytes.
| Exception | Condition |
|---|---|
| ArgumentNullException | bytes is null. |
| ArgumentOutOfRangeException | index or count is less than zero. -or- index and count do not denote a valid range in bytes. -or- The resulting number of bytes is greater than the maximum number that can be returned as an integer. |
| ArgumentException | Error detection is enabled, and bytes contains an invalid sequence of bytes. |
| DecoderFallbackException | A fallback occurred (see Character Encoding in the .NET Framework for complete explanation) -and- DecoderFallback is set to DecoderExceptionFallback. |
To calculate the exact array size required by GetChars to store the resulting characters, call the GetCharCount method. To calculate the maximum array size, call the GetMaxCharCount method. The GetCharCount method generally allocates less memory, while the GetMaxCharCount method generally executes faster.
With error detection, an invalid sequence causes this method to throw an ArgumentException exception. Without error detection, invalid sequences are ignored, and no exception is thrown.
The following example uses the GetCharCount method to return the number of characters produced by decoding a range of elements in a byte array.
using namespace System; using namespace System::Text; int main() { array<Byte>^bytes = {85,84,70,56,32,69,110,99,111,100,105,110,103,32,69,120,97,109,112,108,101}; UTF8Encoding^ utf8 = gcnew UTF8Encoding; int charCount = utf8->GetCharCount( bytes, 2, 8 ); Console::WriteLine( "{0} characters needed to decode bytes.", charCount ); }
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