Export (0) Print
Expand All

XmlWriter.WriteBase64 Method

When overridden in a derived class, encodes the specified binary bytes as Base64 and writes out the resulting text.

Namespace:  System.Xml
Assembly:  System.Xml (in System.Xml.dll)

public abstract void WriteBase64(
	byte[] buffer,
	int index,
	int count
)

Parameters

buffer
Type: System.Byte[]

Byte array to encode.

index
Type: System.Int32

The position in the buffer indicating the start of the bytes to write.

count
Type: System.Int32

The number of bytes to write.

ExceptionCondition
ArgumentNullException

buffer is null.

ArgumentOutOfRangeException

index or count is less than zero.

-or-

The buffer length minus index is less than count.

For example, the byte buffer may contain the binary contents of a GIF image. This clearly would not be valid XML. The Base64 encoding is designed to represent arbitrary byte sequences in a text form comprised of the 65 US-ASCII characters ([A-Za-z0-9+/=]) where each character encodes 6 bits of the binary data. For more information, see Requests for Comments (RFC) 1521 located on the Request for Comments Web site at http://www.rfc-editor.org/.

The following example uses the WriteBase64 method to write Base64 data. The Base64 data is embedded within an <image> element.

public static void Base64EncodeImageFile() {

  int bufferSize = 1000;
  byte[] buffer = new byte[bufferSize];
  int readBytes = 0;
	
  using (XmlWriter writer = XmlWriter.Create("output.xml")) {

       FileStream inputFile = new FileStream(@"C:\artFiles\sunset.jpg",
                                                                    FileMode.OpenOrCreate, FileAccess.Read, FileShare.Read);
       writer.WriteStartDocument();
       writer.WriteStartElement("image");
       BinaryReader br = new BinaryReader(inputFile);
       Console.WriteLine("\r\nWriting Base64 data...");

       do {
          readBytes = br.Read(buffer, 0, bufferSize);
          writer.WriteBase64(buffer, 0, readBytes);
       } while (bufferSize <= readBytes);
       br.Close();
		
    writer.WriteEndElement();// </image>
    writer.WriteEndDocument();
		
  }
}

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC, Xbox 360, Zune

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

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 3.5, 2.0, 1.0

XNA Framework

Supported in: 3.0, 2.0, 1.0

Community Additions

ADD
Show:
© 2015 Microsoft