c# - Sorting a datatable affects reference datatable -

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i have method similar 1 written bellow(this pseudo-code working in c#):

function generatechart(datatable dt) {     datatable dtcharttable = dt;     dtcharttable.defaultview.sort = "somecolumnname";     //remaining functionality }

what above code sorts records in dt. not getting why doing so. note: function called 2 different places. @ 1 place sending datatable object , @ other datatable directly refered 1 stored in session.

that's right. setting dtcharttable variable same memory represented dt variable. so, sorting dtcharttable affects same defaultview property used second .

if don't want behavior create copy of dt using 

datatable dtcharttable = dt.copy();

but costly because in way every datarow duplicated.
possibility creating new dataview 

dataview view = new dataview(dt); view.sort = "somecolumnname";   ......

this doesn't affect original dt.defaultview , can process datarowview new dataview


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