Reader. Close 方法
public: abstract void Close();
public abstract void Close ();
abstract member Close : unit -> unit
Public MustOverride Sub Close ()
在上一次异步操作完成之前调用了 XmlReader 方法。An XmlReader 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."