c# - 保留重新抛出的异常的类型

Question

我正在编写一个对多个流进行操作的类。这是我现在正在做的一个例子

Dictionary<int, int> dict = new Dictionary<int, int>(_Streams.Count);
for (int i = 0; i < _Streams.Count; i++)
{
    try
    {
        dict.Add(i, _Streams[i].Read(buffer, offset, count));
    }
    catch (System.IO.IOException e)
    {
        throw new System.IO.IOException(String.Format("I/O exception occurred in stream {0}", i), e);
    }
    catch (System.NotSupportedException e)
    {
        throw new System.NotSupportedException(String.Format("The reading of the stream {0} is not supported", i), e);
    }
    catch (System.ObjectDisposedException e)
    {
        throw new System.ObjectDisposedException(String.Format("Stream {0} is Disposed", i), e);
    }
}
int? last = null;
foreach (var i in dict)
{
    if (last == null)
        last = i.Value;
    if (last != i.Value)
        throw new ReadStreamsDiffrentExecption(dict);
    last = i.Value;
}
return (int)last;

我想将我的代码简化为

Dictionary<int, int> dict = new Dictionary<int, int>(_Streams.Count);
for (int i = 0; i < _Streams.Count; i++)
{
    try
    {
        dict.Add(i, _Streams[i].Read(buffer, offset, count));
    }
    catch (Exception e)
    {
        throw new Exception(String.Format("Exception occurred in stream {0}", i), e);
    }
}
int? last = null;
foreach (var i in dict)
{
    if (last == null)
        last = i.Value;
    if (last != i.Value)
        throw new ReadStreamsDiffrentExecption(dict);
    last = i.Value;
}
return (int)last;

但是，如果有人试图捕获特定的异常，我的包装器将隐藏 Read 抛出的异常。我怎样才能保留异常类型，添加我的额外信息，但不需要为 try block 中的每个可能的意外事件编写处理程序。

Answer 1

我建议不要完全捕获这些异常...

您添加的信息(大部分)可以从堆栈转储中收集。

您可以使用 catch-and-wrap 转换为特定于库的异常:

 catch (Exception e)
 {
    throw new ReadStreamsErrorExecption(
      String.Format("Exception occurred in stream {0}", i), e);
 }