C# 循环声明类内部的每个事件

Question

我在某处看到过这样的代码。

理想情况下，我想要一个像这样的循环来适应这种 Func 事件类型。

public static event Func<RecentDirectories, DirectoryInfo, Exception, bool> ContinueOnExceptionEvent;

/// <summary>
/// Determine if the loop should continue on a general exception not already handled
/// in the loop's catch statement.
/// </summary>
/// <param name="dir"></param>
/// <param name="e"></param>
/// <returns>True continues loop, false rethrows the exception</returns>
protected virtual bool TryContinueOnException(DirectoryInfo dir, Exception ex)
{
    if (!Aborted) // check if thread aborted before doing event
    {
        if (null != ContinueOnExceptionEvent)
        {
            // foreach line doesn't compile because 
            // ContinueOnExceptionEvent doesn't have a GetEnumerator()
            foreach (var e in ContinueOnExceptionEvent)
            {
                if (e(this, dir, ex))
                {
                    return true;
                }
            }
        }
    }

    return false;
}

我如何让 foreach 获取所有事件并对它们进行迭代？

Answer 1

您可以通过调用 GetInvocationList 访问每个订阅者。

protected virtual bool TryContinueOnException(DirectoryInfo dir, Exception ex)
{
    if (!Aborted)
    {
        var e = ContinueOnExceptionEvent;
        if (e != null)
        {
            var ds = e.GetInvocationList();
            foreach (Func<RecentDirectories, DirectoryInfo, Exception, bool> d in ds)
            {
                if (d(this, dir, ex))
                    return true;
            }
        }
    }
    return false;
}