InvalidOperationException和NullReferenceException

Question

当我调试我的应用程序时，我得到了很多这样的InvalidOperationException和NullReferenceException：

A first chance exception of type 'System.NullReferenceException' occurred in XGen.Framework.DLL
A first chance exception of type 'System.InvalidOperationException' occurred in System.Core.dll
A first chance exception of type 'System.InvalidOperationException' occurred in System.Core.dll
A first chance exception of type 'System.NullReferenceException' occurred in XGen.Framework.DLL
A first chance exception of type 'System.InvalidOperationException' occurred in System.Core.dll
A first chance exception of type 'System.InvalidOperationException' occurred in System.Core.dll
A first chance exception of type 'System.NullReferenceException' occurred in XGen.Framework.DLL
A first chance exception of type 'System.InvalidOperationException' occurred in System.Core.dll
A first chance exception of type 'System.InvalidOperationException' occurred in System.Core.dll
A first chance exception of type 'System.NullReferenceException' occurred in XGen.Framework.DLL
A first chance exception of type 'System.InvalidOperationException' occurred in System.Core.dll
A first chance exception of type 'System.InvalidOperationException' occurred in System.Core.dll
A first chance exception of type 'System.NullReferenceException' occurred in XGen.Framework.DLL
A first chance exception of type 'System.InvalidOperationException' occurred in System.Core.dll
A first chance exception of type 'System.InvalidOperationException' occurred in System.Core.dll
A first chance exception of type 'System.NullReferenceException' occurred in XGen.Framework.DLL
A first chance exception of type 'System.InvalidOperationException' occurred in System.Core.dll
A first chance exception of type 'System.InvalidOperationException' occurred in System.Core.dll
A first chance exception of type 'System.NullReferenceException' occurred in XGen.Framework.DLL

它是如何使应用程序变慢的？

编辑：

找到发生InvalidOperationException的位置

public static Value.Locale Get(string value)
    {
        try
        { return _Items.First(itm => itm.ID.ToUpper() == value.ToUpper() || itm.Name.ToUpper() == value.ToUpper()); }
        catch (Exception)
        { return new XGen.Framework.Value.Locale(); }
    }

翻译的文本:序列不包含匹配的元素

我应该检查_Items.Count是否> 0吗？

Answer 1

如果他们没有让你的程序变慢，那他们应该是例外的。如果您知道您的_items可以为空，这不是异常，这是一个正常的流程，不应该用异常来处理它。您可以检查计数，或者只调用FirstOrDefault而不是First...

Answer 2

它不可能让你的应用程序更快，所以，是的，它会让你的应用程序变慢，但“慢”当然是相对的。我更关心的是这些异常是由于应用程序中的逻辑错误造成的，而不是它的运行速度。

Answer 3

你必须开始缩小范围，弄清楚到底发生了什么。我猜测的原因是这个XGen.Framework.DLL做了一些不好的事情(导致System.Core中的InvalidOperationException )，但却很好地为您处理它，这就是应用程序继续运行的原因。

您可以告诉调试器在第一次更改异常时停止，并检查堆栈跟踪。