c# - How To Convert The DataTable Column type? -


i trying implement:

dtgroupedby.compute("sum(power)",dvv.rowfilter);

it results of error:

invalid usage of aggregate function sum() , type: string.

how convert column type ??

compute method supports expressions , support convert function use inside of expression.

for example, calculate sum of column like

mydatatable.compute("sum(convert(your column name, 'data type'))")

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