ManagementOperationObserver.ObjectReady 事件

定义

新对象可用时发生。

C#
public event System.Management.ObjectReadyEventHandler ObjectReady;

事件类型

示例

以下示例演示如何执行异步实例枚举。 该示例使用 ManagementOperationObserver 类异步处理管理信息和事件。

C#
using System;
using System.Management;

// This example demonstrates how
// to perform an asynchronous instance enumeration.

public class EnumerateInstancesAsync
{
    public EnumerateInstancesAsync()
    {
        // Enumerate asynchronously using Object Searcher
        // ===============================================

        // Instantiate an object searcher with the query
        ManagementObjectSearcher searcher =
            new ManagementObjectSearcher(new
            SelectQuery("Win32_Service"));

        // Create a results watcher object,
        // and handler for results and completion
        ManagementOperationObserver results = new
            ManagementOperationObserver();

        // Attach handler to events for results and completion
        results.ObjectReady += new
            ObjectReadyEventHandler(this.NewObject);
        results.Completed += new
            CompletedEventHandler(this.Done);

        // Call the asynchronous overload of Get()
        // to start the enumeration
        searcher.Get(results);

        // Do something else while results
        // arrive asynchronously
        while (!this.Completed)
        {
            System.Threading.Thread.Sleep (1000);
        }

        this.Reset();
    }

    private bool isCompleted = false;

    private void NewObject(object sender,
        ObjectReadyEventArgs obj)
    {
        Console.WriteLine("Service : {0}, State = {1}",
            obj.NewObject["Name"],
            obj.NewObject["State"]);
    }

    private bool Completed
    {
        get
        {
            return isCompleted;
        }
    }

    private void Reset()
    {
        isCompleted = false;
    }

    private void Done(object sender,
        CompletedEventArgs obj)
    {
        isCompleted = true;
    }

    public static void Main()
    {
        EnumerateInstancesAsync example =
            new EnumerateInstancesAsync();

        return;
    }
}

注解

事件数据

事件处理程序接收 ObjectReadyEventArgs 类型的变量,该变量包含与此事件相关的数据。 以下 ObjectReadyEventArgs 属性提供特定于此事件的信息。

Property 描述
ContextManagementEventArgs) 继承 ( 获取从触发事件的操作反射回的操作上下文。
NewObject 获取新返回的对象。

.NET Framework 安全性

对直接调用方的完全信任。 此成员不能由部分信任的代码使用。 有关详细信息,请参阅 使用部分受信任的代码中的库

适用于

产品 版本
.NET Framework 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1