我应该如何经常使用尝试和catch在C＃中？ [英] How often should I use try and catch in C#?

问题描述

在编写C＃应用程序，它的首要任务是永不死机中，我应该怎么经常使用try-catch块？

When writing a C# application whose #1 priority is to never crash, how often should I used a try-catch block?

我可以封装在一个方法中的所有语句的try-catch块？

Can I encapsulate all the statements in a method in try-catch blocks?

public void SomeMethod()
{
    try
    {
        // entire contents of the function
        // library calls
        // function calls
        // variable initialization .. etc
    }
    catch (Exception e)
    {
        // recover
    }
}

什么缺点在包装的try-catch块的一切吗？

What are the downsides to wrapping everything in try-catch blocks?

推荐答案

唯一的缺点是，当一个异常被抛出实际。没有开销包裹code，除非发生异常时。

The only down side is when an exception is actually thrown. There is no overhead for wrapping the code, except for when exceptions occur.

此外，你不希望使用try / catch语句的控制流。考虑这个（坏code）：

Also, you don't want to use try/catch for control flow. Consider this (bad code):

try {

    FileStream fs = File.Open("somefile.txt", FileMode.Open);

} catch (Exception ex) {
    MessageBox.Show("The file does not exist. Please select another file");
}

您会得到像从一些File.Exists更多的东西表现。如：

You'll get more performance from some thing like File.Exists. such as:

if(!File.Exists("somefile.txt"))
  MessageBox.Show("The file does not exist.")

编辑：
发现 MSDN直接引用：

查找和设计走
  异常沉重code可能导致
  体面PERF取胜。请记住，
  这有没有关系的try / catch
  块：你只收取成本时，
  实际的异常。您
  可以使用尽可能多的try / catch块作为
  你要。使用异常
  无偿为你失去
  性能。例如，您应该
  远离的东西收起来就像使用
  例外的控制流程。

Finding and designing away exception-heavy code can result in a decent perf win. Bear in mind that this has nothing to do with try/catch blocks: you only incur the cost when the actual exception is thrown. You can use as many try/catch blocks as you want. Using exceptions gratuitously is where you lose performance. For example, you should stay away from things like using exceptions for control flow.

这篇关于我应该如何经常使用尝试和catch在C＃中？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！