XmlWriter.WriteStartDocumentAsync Method
Asynchronously writes the XML declaration with the version "1.0".
Namespace: System.Xml
Assembly: System.Xml (in System.Xml.dll)
Return Value
Type: System.Threading.Tasks.TaskThe task that represents the asynchronous WriteStartDocument operation.
| Exception | Condition |
|---|---|
| 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.” |
| InvalidOperationException | An XmlWriter asynchronous method was called without setting the Async flag to true. In this case, InvalidOperationException is thrown with the message “Set XmlWriterSettings.Async to true if you want to use Async Methods.” |
This is the asynchronous version of WriteStartDocument, with the same functionality. To use this method, you must set the Async flag to true.
Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
