将 .NET 事件转换为可观察序列。
              Namespace:System.Reactive.Linq
              装配: System.Reactive.dll) 中的 System.Reactive (
语法
'Declaration
Public Shared Function FromEvent(Of TDelegate, TEventArgs) ( _
    addHandler As Action(Of TDelegate), _
    removeHandler As Action(Of TDelegate) _
) As IObservable(Of TEventArgs)
'Usage
Dim addHandler As Action(Of TDelegate)
Dim removeHandler As Action(Of TDelegate)
Dim returnValue As IObservable(Of TEventArgs)
returnValue = Observable.FromEvent(addHandler, _
    removeHandler)
public static IObservable<TEventArgs> FromEvent<TDelegate, TEventArgs>(
    Action<TDelegate> addHandler,
    Action<TDelegate> removeHandler
)
public:
generic<typename TDelegate, typename TEventArgs>
static IObservable<TEventArgs>^ FromEvent(
    Action<TDelegate>^ addHandler, 
    Action<TDelegate>^ removeHandler
)
static member FromEvent : 
        addHandler:Action<'TDelegate> * 
        removeHandler:Action<'TDelegate> -> IObservable<'TEventArgs> 
JScript does not support generic types and methods.
类型参数
- TDelegate
委托的类型。 
- TEventArgs
事件的类型。 
参数
- addHandler
类型: System.Action<TDelegate>
将给定事件处理程序附加到基础 .NET 事件的操作。 
- removeHandler
类型: System.Action<TDelegate>
将给定事件处理程序与基础 .NET 事件分离的操作。 
返回值
类型: System.IObservable<TEventArgs>
包含基础 .NET 事件调用的数据表示形式的可观察序列。