XmlTextReader.ReadElementContentAsBase64(Byte[], Int32, Int32) Method
Definition
Important
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Reads the element and decodes the Base64 content.
public:
override int ReadElementContentAsBase64(cli::array <System::Byte> ^ buffer, int index, int count);public override int ReadElementContentAsBase64 (byte[] buffer, int index, int count);override this.ReadElementContentAsBase64 : byte[] * int * int -> intPublic Overrides Function ReadElementContentAsBase64 (buffer As Byte(), index As Integer, count As Integer) As IntegerParameters
- buffer
- Byte[]
The buffer into which to copy the resulting text. This value cannot be null.
- index
- Int32
The offset into the buffer where to start copying the result.
- count
- Int32
The maximum number of bytes to copy into the buffer. The actual number of bytes copied is returned from this method.
Returns
The number of bytes written to the buffer.
Exceptions
The buffer value is null.
The current node is not an element node.
The index into the buffer or index + count is larger than the allocated buffer size.
The XmlTextReader implementation does not support this method.
The element contains mixed-content.
The content cannot be converted to the requested type.
Examples
See XmlReader.ReadElementContentAsBase64 to see an example using this method.
Remarks
Note
Starting with the .NET Framework 2.0, we recommend that you create XmlReader instances by using the XmlReader.Create method to take advantage of new functionality.
This method reads the element content, decodes it using Base64 encoding, and returns the decoded binary bytes (for example, an inline Base64 encoded GIF image) into the buffer. For more information, see RFC 1521, "MIME (Multipurpose Internet Mail Extensions) Part One: Mechanisms for Specifying and Describing the Format of Internet Message Bodies". You can obtain RFCs from the Request for Comments Web site.
This method can only read simple-content elements. The element can contain text, white space, significant white space, CDATA sections, comments and processing instructions. It can also contain entity references, which are automatically expanded. The element cannot have child elements.
This method is very similar to the ReadContentAsBase64 method except that it can only be called on element node types.
If the count value is higher than the number of bytes in the document, or if it is equal to the number of bytes in the document, the XmlTextReader reads all the remaining bytes in the document and returns the number of bytes read. The next XmlTextReader method call returns a zero and moves the reader to the node following the EndElement.
If you call Read before all of the element content is consumed, the reader may behave as if the first content was consumed and then the Read method was called. This means that the reader reads all the text until the end element is encountered. It then reads the end tag node, reads the next node, and then positions itself on the next subsequent node.
