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XmlReader.ReadElementContentAsDouble Method

Definition

Reads the current element and returns the contents as a double-precision floating-point number.

Overloads

ReadElementContentAsDouble()

Reads the current element and returns the contents as a double-precision floating-point number.

ReadElementContentAsDouble(String, String)

Checks that the specified local name and namespace URI matches that of the current element, then reads the current element and returns the contents as a double-precision floating-point number.

ReadElementContentAsDouble()

Source:
XmlReader.cs
Source:
XmlReader.cs
Source:
XmlReader.cs

Reads the current element and returns the contents as a double-precision floating-point number.

public:
 virtual double ReadElementContentAsDouble();
public virtual double ReadElementContentAsDouble ();
abstract member ReadElementContentAsDouble : unit -> double
override this.ReadElementContentAsDouble : unit -> double
Public Overridable Function ReadElementContentAsDouble () As Double

Returns

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

Exceptions

The XmlReader is not positioned on an element.

-or-

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."

The current element contains child elements.

-or-

The element content cannot be converted to a double-precision floating-point number.

The method is called with null arguments.

Examples

The following example uses the method to return the element content as a double-precision floating-point number.

using (XmlReader reader = XmlReader.Create("dataFile.xml")) {
     reader.ReadToFollowing("double");
     Double number = reader.ReadElementContentAsDouble();
     // Do some processing with the number object.	
}
Using reader As XmlReader = XmlReader.Create("dataFile.xml")
  reader.ReadToFollowing("double")
  Dim number As [Double] = reader.ReadElementContentAsDouble()
  ' Do some processing with the number object.
End Using

The example uses the dataFile.xml file as input.

<root>
  <stringValue>
     <!--comment-->
     <?some pi?>
      text value of the element.
  </stringValue>
  <longValue>270000000000001</longValue>
  <number>0</number>
  <double>2E10</double>
  <date>2003-01-08T15:00:00-00:00</date>
</root>

Remarks

This method reads the start tag, the contents of the element, and moves the reader past the end element tag. It expands entities and ignores processing instructions and comments. The element can only contain simple content. That is, it cannot have child elements.

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.

For more information, see the Remarks section of the XmlReader reference page.

Applies to

ReadElementContentAsDouble(String, String)

Source:
XmlReader.cs
Source:
XmlReader.cs
Source:
XmlReader.cs

Checks that the specified local name and namespace URI matches that of the current element, then reads the current element and returns the contents as a double-precision floating-point number.

public:
 virtual double ReadElementContentAsDouble(System::String ^ localName, System::String ^ namespaceURI);
public virtual double ReadElementContentAsDouble (string localName, string namespaceURI);
abstract member ReadElementContentAsDouble : string * string -> double
override this.ReadElementContentAsDouble : string * string -> double
Public Overridable Function ReadElementContentAsDouble (localName As String, namespaceURI As String) As Double

Parameters

localName
String

The local name of the element.

namespaceURI
String

The namespace URI of the element.

Returns

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

Exceptions

The XmlReader is not positioned on an element.

-or-

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."

The current element contains child elements.

-or-

The element content cannot be converted to the requested type.

The method is called with null arguments.

The specified local name and namespace URI do not match that of the current element being read.

Remarks

This method reads the start tag, the contents of the element, and moves the reader past the end element tag. It expands entities and ignores processing instructions and comments. The element can only contain simple content. That is, it cannot have child elements.

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.

For more information, see the Remarks section of the XmlReader reference page.

Applies to