#583 – You Can’t Modify the Iterator Variable Within a foreach Loop

The iterator variable within a foreach loop is the variable that takes on the value of each item within the corresponding collection, each time through the loop.

            string[] puppets =
                {"Crow T. Robot", "Howdy Doody", "Kermit",
                 "King Friday XIII", "Lamb Chop"};

            // nextPuppet is the iterator variable
            foreach (string nextPuppet in puppets)
                Console.WriteLine("Puppet: {0}", nextPuppet);

If you try to modify this iterator variable within the loop, however, you’ll get a compile-time error.

foreach (string nextPuppet in puppets)
    nextPuppet = "(" + nextPuppet + ")";
    Console.WriteLine("Puppet: {0}", nextPuppet);


About Sean
Software developer in the Twin Cities area, passionate about .NET technologies. Equally passionate about my own personal projects related to family history and preservation of family stories and photos.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: