XmlWriter.WriteStartElementAsync(String, String, String) 方法
定义
异步写入指定的开始标记并将其与给定的命名空间和前缀关联起来。Asynchronously writes the specified start tag and associates it with the given namespace and prefix.
public:
virtual System::Threading::Tasks::Task ^ WriteStartElementAsync(System::String ^ prefix, System::String ^ localName, System::String ^ ns);
public virtual System.Threading.Tasks.Task WriteStartElementAsync (string prefix, string localName, string ns);
public virtual System.Threading.Tasks.Task WriteStartElementAsync (string? prefix, string localName, string? ns);
abstract member WriteStartElementAsync : string * string * string -> System.Threading.Tasks.Task
override this.WriteStartElementAsync : string * string * string -> System.Threading.Tasks.Task
Public Overridable Function WriteStartElementAsync (prefix As String, localName As String, ns As String) As Task
参数
- prefix
- String
元素的命名空间前缀。The namespace prefix of the element.
- localName
- String
元素的本地名称。The local name of the element.
- ns
- String
与元素关联的命名空间 URI。The namespace URI to associate with the element.
返回
表示 WriteStartElement 异步操作的任务。The task that represents the asynchronous WriteStartElement operation.
例外
在上一次异步操作完成之前调用了 XmlWriter 方法。An XmlWriter method was called before a previous asynchronous operation finished. 在此情况下,会引发 InvalidOperationException 并显示消息“异步操作已在进行中。”In this case, InvalidOperationException is thrown with the message "An asynchronous operation is already in progress."
- 或 --or-
调用了 XmlWriter 异步方法,但未将 Async 标志设置为 true。An XmlWriter asynchronous method was called without setting the Async flag to true. 在这种情况下,将引发 InvalidOperationException 并显示消息“如果要使用异步方法,请将 XmlWriterSettings.Async 设置为 true”。In this case, InvalidOperationException is thrown with the message "Set XmlWriterSettings.Async to true if you want to use Async Methods."
注解
这是的异步版本 WriteStartElement ,具有相同的功能。This is the asynchronous version of WriteStartElement, with the same functionality. 若要使用此方法,必须将 Async 标志设置为 true 。To use this method, you must set the Async flag to true.