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I am stepping through a large list of object to do some stuff regarding said objects in the list.
During my iteration, I will remove some objects from the list depending on certain criteria.
Once all is done, I need to update the UI regarding the number of objects in my list. (List of T).
QUESTION:
When I call list.count, does .net actually iterate through the list to count it, or does it store the count as a property/variable?
If .net physically re-iterates through the list, I may just as well keep a counter on my own iteration through the list, and save the overhead?
Thanks
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We often want to perform the same operation on every element in a list, like displaying each element or manipulating them mathematically. To do that, we can use a loop to iterate over each element, repeating the same code for each element.
A for loop iterates through items the same way as while and do-while loops, but it can also iterate through a list or set.
It simply keeps an internal int to track the number of items. So no iteration. The documentation says retrieving Count is an O(1) operation:
http://msdn.microsoft.com/en-us/library/27b47ht3%28v=vs.110%29.aspx
You can see for yourself:
http://referencesource.microsoft.com/#mscorlib/system/collections/generic/list.cs
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