XmlWriter.WriteSurrogateCharEntity(Char, Char) Method

Definition

Namespace:

System.Xml

Assembly:

System.Xml.ReaderWriter.dll

Source:

XmlWriter.cs

When overridden in a derived class, generates and writes the surrogate character entity for the surrogate character pair.

public:
 abstract void WriteSurrogateCharEntity(char lowChar, char highChar);

public abstract void WriteSurrogateCharEntity (char lowChar, char highChar);

abstract member WriteSurrogateCharEntity : char * char -> unit

Public MustOverride Sub WriteSurrogateCharEntity (lowChar As Char, highChar As Char)

Parameters

lowChar

Char

The low surrogate. This must be a value between 0xDC00 and 0xDFFF.

highChar

Char

The high surrogate. This must be a value between 0xD800 and 0xDBFF.

Exceptions

ArgumentException

An invalid surrogate character pair was passed.

InvalidOperationException

An XmlWriter method was called before a previous asynchronous operation finished. In this case, InvalidOperationException is thrown with the message "An asynchronous operation is already in progress."

Remarks

This method is only applicable on systems that use UTF-16 encoding.

The surrogate character entity is written in hexadecimal format. The range for surrogate characters is #x10000 to #x10FFFF. The following formula is used to generate the surrogate character entity: (highChar -0xD800) * 0x400 + (lowChar -0xDC00) + 0x10000

For both HTML and XML, the document character set (and therefore the notation of numeric character references) is based on UCS [ISO-10646]. A single numeric character reference in a source document may therefore in some cases correspond to two 16-bit units in a string (a high surrogate and a low surrogate). These 16-bit units are referred to as a surrogate pair.

For more information regarding surrogates or characters, refer to section 3.7 of the Unicode 3.0/Unicode 2.0 standard located at https://www.unicode.org, or section 2.2 of the W3C XML 1.0 Recommendation.

For the asynchronous version of this method, see WriteSurrogateCharEntityAsync.