ArgumentException或ArgumentNullException为字符串参数？ [英] ArgumentException or ArgumentNullException for string parameters?

问题描述

在最佳实践中，哪个更好：

Far as best practices are concerned, which is better:

public void SomeMethod(string str) 
{
    if(string.IsNullOrEmpty(str))
    {
        throw new ArgumentException("str cannot be null or empty.");
    }

    // do other stuff
}

或

public void SomeMethod(string str) 
{
    if(str == null) 
    {
        throw new ArgumentNullException("str");
    }

    if(str == string.Empty)
    {
        throw new ArgumentException("str cannot be empty.");
    }

    // do other stuff
}

第二个版本似乎更精确，但也比第一个更麻烦。我通常去＃1，但是我想检查是否有一个参数为＃2。

The second version seems more precise, but also more cumbersome than the first. I usually go with #1, but figured I'd check if there's an argument to be made for #2.

推荐答案

我说第二种方式确实更精确 - 是的，这样比较麻烦，但是你可以随时把它包装起来，以避免一直都这样做。甚至可以是一个扩展方法：

I'd say the second way is indeed more precise - yes, it's more cumbersome but you can always wrap it in a method to avoid having to do it all the time. It could even be an extension method:

str.ThrowIfNullOrEmpty("str");


public static void ThrowIfNullOrEmpty(this string value, string name)
{
    if (value == null)
    {
        throw new ArgumentNullException(name);
    }
    if (value == "")
    {
        throw new ArgumentException("Argument must not be the empty string.",
                                    name);
    }
}

另一种潜在有用的表单是返回原来的字符串，如果一切正常。你可以这样写：

Another form which is potentially useful is one which returns the original string if everything is okay. You could write something like this:

public Person(string name)
{
    this.name = name.CheckNotEmpty();
}

另一个需要考虑的选项是使用代码合同作为替代您自己的例外。

Another option to consider is using Code Contracts as an alternative to throwing your own exceptions.

这篇关于ArgumentException或ArgumentNullException为字符串参数？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！