.net - Boxing/unboxing in DataTables and LINQ -

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let's i've got memory-based datatable this:

datatable dt = new datatable(); dt.columns.add("c1", system.type.gettype("system.double")); dt.columns.add("c2", system.type.gettype("system.double")); ...  datarow row = dt.addrow(); row["c1"] = 1; row["c2"] = 2; ...

then query table:

list<datarow> rows = (from r in table (double)r["c1"] < 2.0 select r).tolist();

and in profiler see creates lot of doubles. assume somehow related comparison.

any ideas how rid of needless memory allocation?

i use .net 4, vs 2010, c#.

the underlying storage here in typed array (in case in doublestorage class), access goes via object, since there no generic api. cannot avoid boxing unless switch class-based model without datatable.


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