c# - 如何覆盖未标记为虚拟的事件处理程序？

Question

我必须创建一个继承自 FileSystemWatcher 的类。我应该拦截事件 OnCreated 并创建我自己的事件 OnCreated。我试过如下:

public class LocalFolderWatcher : FileSystemWatcher, IWatcher
{
    ...
    public event LocalFolderEventHandler Created;

    protected override void OnCreated(FileSystemEventArgs e)
    {
        string path = System.IO.Path.GetDirectoryName(e.FullPath);
        LocalFolderEventArgs args = new LocalFolderEventArgs(e.ChangeType, this._gatewayConfigurationName, path, this._folderConfigurationName, e.Name);

        if (Created != null && base.EnableRaisingEvents && base.Path != null)
            Created(this, args);

        base.OnCreated(e);
    }
}

但我得到一个错误:我无法覆盖未标记为虚拟、抽象或覆盖的方法。我试图用"new"替换“覆盖”，但这样就不会引发事件..

如何拦截真正的“OnCreated”并替换为我的？

谢谢

Answer 1

您不需要替换OnCreated，只需创建您自己的处理程序并将其传递给Created 事件即可。

public class LocalFolderWatcher : FileSystemWatcher, IWatcher
{
    //...
    public event LocalFolderEventHandler CustomCreated;

    public LocalFolderWatcher()
    {
        Created += OnCreated;
    }

    private new void OnCreated(object sender, FileSystemEventArgs e)
    {
        string path = System.IO.Path.GetDirectoryName(e.FullPath);
        LocalFolderEventArgs args = new LocalFolderEventArgs(e.ChangeType, this._gatewayConfigurationName, path, this._folderConfigurationName, e.Name);

        if (CustomCreated != null && base.EnableRaisingEvents && base.Path != null)
            CustomCreated(this, args);
    }
}