UTF8Encoding.GetByteCount Method (String)

Calculates the number of bytes produced by encoding the characters in the specified String.

Namespace:  System.Text
Assembly:  mscorlib (in mscorlib.dll)

public override int GetByteCount(
	string chars
)

Parameters

chars
Type: System.String

The String containing the set of characters to encode.

Return Value

Type: System.Int32
The number of bytes produced by encoding the specified characters.

ExceptionCondition
ArgumentNullException

chars is null.

ArgumentOutOfRangeException

The resulting number of bytes is greater than the maximum number that can be returned as an integer.

ArgumentException

Error detection is enabled, and chars contains an invalid sequence of characters.

EncoderFallbackException

A fallback occurred (see Character Encoding in the .NET Framework for complete explanation)

-and-

EncoderFallback is set to EncoderExceptionFallback.

To calculate the exact array size required by GetBytes to store the resulting bytes, the application uses GetByteCount. To calculate the maximum array size, the application should use GetMaxByteCount. The GetByteCount method generally allows allocation of less memory, while the GetMaxByteCount method generally executes faster.

With error detection, an invalid sequence causes this method to throw a ArgumentException. Without error detection, invalid sequences are ignored, and no exception is thrown.

NoteNote

To ensure that the encoded bytes are decoded properly, the application should prefix encoded bytes with a preamble.

The following example demonstrates how to use the GetByteCount method to return the number of bytes required to encode a String using UTF8Encoding.

using System;
using System.Text;

class UTF8EncodingExample {
    public static void Main() {
        String chars = "UTF8 Encoding Example";

        UTF8Encoding utf8 = new UTF8Encoding();
        int byteCount = utf8.GetByteCount(chars);
        Console.WriteLine(
            "{0} bytes needed to encode string.", byteCount
        );
    }
}

.NET Framework

Supported in: 4.5.2, 4.5.1, 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Portable Class Library

Supported in: Portable Class Library

.NET for Windows Store apps

Supported in: Windows 8

.NET for Windows Phone apps

Supported in: Windows Phone 8.1, Windows Phone 8, Silverlight 8.1

Windows Phone 8.1, Windows Phone 8, Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

Was this page helpful?
(1500 characters remaining)
Thank you for your feedback
Show:
© 2014 Microsoft