XmlReader.ReadContentAsDouble Method

Definition

Namespace:

System.Xml

Assembly:

System.Xml.ReaderWriter.dll

Source:

XmlReader.cs

Reads the text content at the current position as a double-precision floating-point number.

public:
 virtual double ReadContentAsDouble();

public virtual double ReadContentAsDouble ();

abstract member ReadContentAsDouble : unit -> double
override this.ReadContentAsDouble : unit -> double

Public Overridable Function ReadContentAsDouble () As Double

Returns

Double

The text content as a double-precision floating-point number.

Exceptions

InvalidCastException

The attempted cast is not valid.

FormatException

The string format is not valid.

InvalidOperationException

An XmlReader 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 concatenates text, white space, significant white space, and CDATA sections, and skips any comments or processing instructions. Entity references are automatically resolved.

If the content is typed xsd:double, the reader returns a double-precision floating-point number. If the content is not typed xsd:double, the reader attempts to convert it to a double-precision floating-point number according to the rules defined by the W3C XML Schema Part 2: Datatypes recommendation.

The following table describes how this method treats each node type.

XmlNodeType	Return value	Reader behavior
Text CDATA Whitespace SignificantWhitespace EntityReference EndEntity	Concatenated content of text, CDATA, white space and significant white space nodes converted to the requested type.	Moves to the next start element or end element tag. Entity references are automatically expanded.
Attribute	Same as calling XmlConvert.ToXxx on the attribute value.	The reader remains in the current position.
Comment ProcessingInstruction	Ignores the processing instruction (PI) or comment and reads the concatenated text content that follows the PI or comment.	Moves to the next start element or end element tag. Entity references are automatically expanded.
EndElement	An empty string.	The reader remains in the current position.
Element XmlDeclaration None Document DocumentType Notation Entity DocumentFragment	An InvalidOperationException is thrown.	Undefined, although typically the reader remains in the current position.

For more information, see the XmlReader reference page and the W3C XML Schema Part 2: Datatypes recommendation.