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LINQ - Removing elements in source list prevents enumeration of "c

Hello, I have a list of elements and I want to perform an operation on a
subset of them and then remove them from the list.

If I build a sequence of elements via LINQ to drive the enumeration, as soon
as I remove the first element the enumeration operation is broken.

This surprises me. I thought the LINQ'd sequence would be its own
collection, impervious to changes in the original source collection.
Mar 4 '08 #1
2 1409
Jon, do you need a place to live? We'll provide food, shelter and beer, in
exchange for a brain tap.

Thank you.

"Jon Skeet [C# MVP]" wrote:
No - LINQ streams the data (when it can), so it will still be asking
the original data source for data as it goes.
Mar 4 '08 #2
Jon Skeet [C# MVP] wrote:
Todd Beaulieu <To**********@d iscussions.micr osoft.comwrote:
Hello, I have a list of elements and I want to perform an operation
on a subset of them and then remove them from the list.
If I build a sequence of elements via LINQ to drive the
enumeration, as soon as I remove the first element the enumeration
operation is broken.

This surprises me. I thought the LINQ'd sequence would be its own
collection, impervious to changes in the original source collection.

No - LINQ streams the data (when it can), so it will still be asking
the original data source for data as it goes.
Only outside a db. Any linq-access to a db isn't streamed but batched
(i.e.: fetch everything to the client)

FB

--
------------------------------------------------------------------------
Lead developer of LLBLGen Pro, the productive O/R mapper for .NET
LLBLGen Pro website: http://www.llblgen.com
My .NET blog: http://weblogs.asp.net/fbouma
Microsoft MVP (C#)
------------------------------------------------------------------------
Mar 5 '08 #3

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