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c#validationguard-clause

Refactoring Guard Clauses


What approaches do people take (if any) in managing guard clause explosion in your classes? For example:

public void SomeMethod<T>(string var1, IEnumerable<T> items, int count)
{
    if (string.IsNullOrEmpty(var1))
    {
        throw new ArgumentNullException("var1");
    }

    if (items == null)
    {
        throw new ArgumentNullException("items");
    }

    if (count < 1)
    {
        throw new ArgumentOutOfRangeException("count");
    }

    ... etc ....
}

In the project that I am currently working on there are many classes that have a similar set of guard clauses on the public methods.

I am aware of the .NET 4.0 Code Contracts however this is not an option for our team at the moment.


Solution

  • A lot of projects that I've seen use a static Guard class.

    public static class Guard {
        public static void ArgumentIsNotNull(object value, string argument) {
            if (value == null)
                throw new ArgumentNullException(argument);
        }
    }
    

    It makes the code a lot cleaner, in my opinion.

    Guard.ArgumentIsNotNull(arg1, "arg1");