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c# - Remove all columns with no data from DataTable

If all the items for a particular column are empty, I want to remove that column from the DataTable. What's the most elegant way to do this operation on all columns in the DataTable?

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You can use the Compute method, like this:

if (table.Compute("COUNT(ColumnName)", "ColumnName <> NULL") == 0)
    table.Columns.Remove("ColumnName");

Alternatively, you can use LINQ:

if (table.AsEnumerable().All(dr => dr.IsNull("ColumnName")))
    table.Columns.Remove("ColumnName");

EDIT: To completely answer the question:

foreach(var column in table.Columns.Cast<DataColumn>().ToArray()) {
    if (table.AsEnumerable().All(dr => dr.IsNull(column)))
        table.Columns.Remove(column);
}

You need to call ToArray because the loop will modify the collection.


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