使用内部异常或创建基异常的派生类型

如果有一个方法调用了许多其他方法,并且它们都可以抛出从ArgumentExceptions到EndOfStreamExceptions的各种异常,那么最好执行catch-all并将其封装在自己的异常中,然后设置内部异常,或者创建基类异常并抛出派生类型。如果抛出的派生类型违背了在可能的情况下重用BCL异常的建议。例如

public void A()
{
    if (someCondition)
    {
        throw new ArgumentException()
    }
}

public void B()
{
    if (anotherCondition)
    {
        throw new InvalidOperation()
    }
}

public void C()
{
    // Throws format exception
    int.Parse(x);
}

public void DoSomething()
{
    try
    {
        A();
        B();
        C();
    }
    catch(Exception ex)
    {
        throw new DoSomethingException("Could not complete DoSomthing"){ InnerException = ex};
    }
}

还是最好做一些类似的事情

public void DoSomething()
{
    A();
    B();
    C();
    D();
}

public void A()
{
    if (someCondition)
    {
        throw new DoSomethingMissingArg()
    }
}

public void B()
{
    if (anotherCondition)
    {
        throw new DoSomethingCannotStart()
    }
}

public void C()
{
    // Throws format exception
    if (!int.TryParse(x))
    {
        throw new DoSomethingFormatException("x must be in y format");
    }
}

public class DoSomethingException: Exception
{

}

public class DoSomethingMissingArg: DoSomethingException
{
    public DoSomethingMissingArg(){ }
}

public class DoSomethingCannotStart: DoSomethingException
{
    public DoSomethingCannotStart(){ }
}

public class DoSomethingFormatException: DoSomethingException
{
    public DoSomethingFormatException(){ }
}