list<rectangle[]> array grouping

I have an array of rectangle elements. each element in the array can be able to represent several diffrent rectangles in it. i would want to find out how can i group similar list items and show their count. e.g the list contains 10 rectangle arrays. of the 10 there are 4 elements which are similar (i.e 4 rectangle elements with the same number, size, orientation of the rectangles in it) for the example i would love to have an end 开发者_JS百科result which shows a list of 7 alements and the count eg. the 6 single elements and the 7th elements showing a count of 4. c# or vb.net

If you can override Equals on your rectangle to determine when you consider two rectangles equal, you could do the following Linq query.

        List<Rectangle[]> rectangleArr;
        var query = (from r in rectangleArr.Cast<Rectangle>()
                     group r by r into gr
                     select new { Count = gr.Count(), Value = gr.Key });
        foreach (var item in query)
        {
            Console.WriteLine("Item: {0}, Count: {1}", item.Value, item.Count);
        }

If you don't want an anonymous type you could create a class:

class RectangleGroup
{
    public Rectangle Value { get; set; }
    public int Count { get; set; }
}

then select like this:

select new RectangleGroup() { Count = gr.Count(), Value = gr.Key }

You can use Tuple:

List<Rectangle> l = new List<Rectangle>();
l.Add(new Rectangle(1, 2, 3, 4));
l.Add(new Rectangle(1, 2, 3, 4));
l.Add(new Rectangle(10, 20, 30, 40));

var grouped = l
    .GroupBy(item => item)
    .Select(group => new Tuple<Rectangle, int>(group.Key, group.Count()));

foreach (var t in grouped)
{
    Console.WriteLine("There are {0} rectangles like {1}.", t.Item2, t.Item1);
}