Question

我试图找出使用try-catch语句处理C＃中的异常的最佳途径，这有点令人沮丧。我想拥有代码，所以如果尝试打开注册表项时抛出异常，那么它将转到下一个注册表项。我能想到的唯一方法是将每个函数调用封装在try-catch语句中，但对我而言，这似乎还有很长的路要走。

还有其他办法吗？
你能在一个try-catch语句中拥有所有代码吗？当发生异常时，让它移动到下一行代码（如跳过）？
我知道这可能是一个no，但是如果在参数中设置了变量，ScanSubKey函数是否可以用来检查异常？

没有try-catch语句

ScanSubKey(Registry.ClassesRoot);
ScanSubKey(Registry.LocalMachine.OpenSubKey("SOFTWARE"));
ScanSubKey(Registry.CurrentUser.OpenSubKey("SOFTWARE"));
if (Is64BitOS)
{
    ScanSubKey(Registry.ClassesRoot.OpenSubKey("Wow6432Node"));
    ScanSubKey(Registry.LocalMachine.OpenSubKey("SOFTWARE\\Wow6432Node"));
    ScanSubKey(Registry.CurrentUser.OpenSubKey("SOFTWARE\\Wow6432Node"));
}

示例

try {
    ScanSubKey(Registry.ClassesRoot);
} 
catch (Exception ex) {
    Debug.WriteLine("The following error occurred opening a registry key: " + ex.Message);
}
try {
    ScanSubKey(Registry.LocalMachine.OpenSubKey("SOFTWARE"));
} 
catch (Exception ex) {
    Debug.WriteLine("The following error occurred opening a registry key: " + ex.Message);
}
try {
    ScanSubKey(Registry.CurrentUser.OpenSubKey("SOFTWARE"));
} 
catch (Exception ex) {
    Debug.WriteLine("The following error occurred opening a registry key: " + ex.Message);
}

if (Is64BitOS)
{
    try {
        ScanSubKey(Registry.ClassesRoot.OpenSubKey("Wow6432Node"));
    } 
    catch (Exception ex) {
        Debug.WriteLine("The following error occurred opening a registry key: " + ex.Message);
    }
    try {
        ScanSubKey(Registry.LocalMachine.OpenSubKey("SOFTWARE\\Wow6432Node"));
    } 
    catch (Exception ex) {
        Debug.WriteLine("The following error occurred opening a registry key: " + ex.Message);
    }
    try {
        ScanSubKey(Registry.CurrentUser.OpenSubKey("SOFTWARE\\Wow6432Node"));
    } 
    catch (Exception ex) {
        Debug.WriteLine("The following error occurred opening a registry key: " + ex.Message);
    }
}

Answer 1

也许这会是一个更好的方法：

public bool TryOpenRegKey(RegistryKey regKey, string subKey = default(string))
{
  try
  {
    if (string.IsNullOrWhiteSpace(subKey))
      ScanSubKey(regKey);
    else
      ScanSubKey(regKey.OpenSubKey(subKey));

    return true;
  }
  catch(Exception ex)
  {
    Debug.WriteLine("The following error occurred opening a registry key: " + ex.Message);
    return false;
  }
}

然后：

TryOpenRegKey(Registry.ClassesRoot);
TryOpenRegKey(Registry.LocalMachine, "SOFTWARE");
TryOpenRegKey(Registry.CurrentUser, "SOFTWARE");

if (Is64BitOS)
{
  TryOpenRegKey(Registry.ClassesRoot, "Wow6432Node");
  TryOpenRegKey(Registry.LocalMachine, "SOFTWARE\\Wow6432Node");
  TryOpenRegKey(Registry.CurrentUser, "SOFTWARE\\Wow6432Node");
}

Answer 2

创建新方法TryScanSubKey。然后你的代码再次看起来很干净：

TryScanSubKey(Registry.ClassesRoot);
TryScanSubKey(Registry.LocalMachine.OpenSubKey("SOFTWARE"));
TryScanSubKey(Registry.CurrentUser.OpenSubKey("SOFTWARE"));
if (Is64BitOS)
{
    TryScanSubKey(Registry.ClassesRoot.OpenSubKey("Wow6432Node"));
    TryScanSubKey(Registry.LocalMachine.OpenSubKey("SOFTWARE\\Wow6432Node"));
    TryScanSubKey(Registry.CurrentUser.OpenSubKey("SOFTWARE\\Wow6432Node"));
}

TryScanSubKey的实施应该是显而易见的，但是，为了完整起见，这里是：

void TryScanSubKey(RegistryKey key)
{
    try
    {
        ScanSubKey(key);
    } 
    catch (Exception ex)
    {
        Debug.WriteLine("The following error occurred opening a registry key: " + ex.Message);
    }
}

请注意，一般，吞下错误是不好的做法，吞下所有错误的情况更糟。因此，请考虑（至少）用更具体的内容替换catch (Exception ex)，例如catch (TheSpecificExceptionThrownByScanSubKey ex)。

Answer 3

我称之为“执行者”：

    public static void Execute(Action action)
    {
        try
        {
            action();
        }
        catch (Exception ex)
        {
        }
    }

然后使用它：

Execute(() => ScanSubKey(Registry.ClassesRoot));

Answer 4

您是否考虑在ScanSubKey函数本身内部放置try / catch并在发生错误时返回？

更少尝试捕获语句？

4 个答案: