1) Yes, you may set formatting for a complete column in the worksheet. You should create a Style object, specify your formatting attribute for the Style object, create StyleFlag object and make the relevant attributes on with respect to Style formattings. Now use Column.ApplyStyle(style, flag) method to set the formatting for the column. Repeat this procedure (or loop through your desired column indexes in the sheet).
See the topic for your reference:
2) Please see the topic (especially check the description under “Protect a Column in the Worksheet” sub-topic): http://www.aspose.com/documentation/.net-components/aspose.cells-for-.net/protecting-worksheets.html
Also for advanced protection settings, see the topic:
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