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    <p>You could project the group number onto each item in the original list using <code>Select</code> and an anonymous type like this:</p> <pre><code>var assigned = Class.Students.Select( (item, index) =&gt; new { Student = item, GroupNumber = index / 20 + 1 }); </code></pre> <p>Then you can use it like this:</p> <pre><code>foreach (var item in assigned) { Console.WriteLine("Student = " + item.Student.Name); Console.WriteLine("You belong to Group " + item.GroupNumber.ToString()); } </code></pre> <p>Or if you wanted to pick off a particular group.</p> <pre><code>foreach (var student in assigned.Where(x =&gt; x.GroupNumber == 5)) { Console.WriteLine("Name = " + student.Name); } </code></pre> <p>Or if you wanted to actually group them to perform aggregates</p> <pre><code>foreach (var group in assigned.GroupBy(x =&gt; x.GroupNumber)) { Console.WriteLine("Average age = " + group.Select(x =&gt; x.Student.Age).Average().ToString()); } </code></pre> <p>Now if you just want to lump the items in batches and you do not care about having the batch number information you can create this simple extension method.</p> <pre><code>public static IEnumerable&lt;IEnumerable&lt;T&gt;&gt; Batch&lt;T&gt;(this IEnumerable&lt;T&gt; target, int size) { var assigned = target.Select( (item, index) =&gt; new { Value = item, BatchNumber = index / size }); foreach (var group in assigned.GroupBy(x =&gt; x.BatchNumber)) { yield return group.Select(x =&gt; x.Value); } } </code></pre> <p>And you could use your new extension method like this.</p> <pre><code>foreach (var batch in Class.Students.Batch(20)) { foreach (var student in batch) { Console.WriteLine("Student = " + student.Name); } } </code></pre>
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    1. POHow do I segment the elements iterated over in a foreach loop
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    1. USBrian Gideon
    1. USBrian Gideon
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    1. COYou made the same mistake as many other posters who have since deleted their responses. You don't take 20 items in a row; each of the first twenty students will all be in a different group!
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      1. USMikeP
    2. COAdditionally, you're not actually grouping anything either. If you want to iterate the students in a group, your method leaves you high and dry.
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      1. USMikeP
    3. CO@MikeP: Yep, nice catch. Fixed. I also renamed `grouped` to `assigned` to better reflect what actually happens. If the OP really wanted to iterate students from a particular group you could do `assigned.Where(x => x.GroupNumber == value)` or `assigned.GroupBy(x => x.GroupNumber)`, though that doesn't look necessary based on what I see in the question. I guess one fun aspect of LINQ is that there are a lot of ways of doing the same thing. Anyway, yeah, I totally choked on the `%` thing instead of `/`.
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      1. USBrian Gideon
 

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