foreach(... in ...) or .ForEach(); that is the question [duplicate]

Question

Possible Duplicate:
C# foreach vs functional each

This is a question about coding for readability.

I have an XDocument and a List<string> of the names of the elements that contain sensitive information that I need to mask (replace with underscores in this example).

XDocument xDoc;
List<string> propertiesToMask;

This can be written in two ways, using traditional foreach loops, or using .ForEach methods with lamba syntax.

foreach (string propertyToMask in propertiesToMask)
{
    foreach (XElement element in xDoc.Descendants(propertyToMask))
    {
        element.SetValue(new string('_', element.Value.Length));
    }
}

or

propertiesToMask
    .ForEach(propertyToMask => xDoc.Descendants(propertyToMask).ToList()
        .ForEach(element => element.SetValue(new string('_', element.Value.Length))));

Which approach do you think is the most readable, and why? If you prefer the second example, how would you present it for maximum readability?

Answer 1

foreach (string propertyToMask in propertiesToMask)
{
    foreach (XElement element in xDoc.Descendants(propertyToMask))
    {
        element.SetValue(new string('_', element.Value.Length));
    }
}

Because the spacing makes it very simple to scan. The second is far to cluttered and I have to actually read it.

Answer 2

Eric Lippert has a good entry about this on his blog. To summarize, the very task done by ForEach is to produce side effects which may not be a desirable thing to do with the functional style of programming in C#.