How to prevent modifications of specific cells?

Is it possible to prevent user-made modifications of some 开发者_StackOverflowspecific cells? I can use VSTO add-in for plugging into Excel events.

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Take a look at Worksheet.Change Event. This event takes a Range object. As far as I remember this objects contains information about what cell(s) is selected. Then you can do with this cell whatever you want link.

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My approach is slightly different.

I protect the complete sheet and then unlock particular cells or columns or rows, so user can fill details in those sheets. But you should get same results with this.

Code has been tested on VS 2008.

private void ThisAddIn_Startup(object sender, System.EventArgs e)
        {

            var activesheet = (Excel.Worksheet)this.Application.ActiveSheet;


            // keep particular cell unlocked 
            activesheet.get_Range("A1",missing).Locked = false;

            // keep entire row unlocked 

            activesheet.get_Range("B2", missing).EntireRow.Locked = false;

            // keep entire column unlocked 

            activesheet.get_Range("C1", missing).EntireColumn.Locked = false;

            // keep particular range (D4 - E8) unlocked 

            activesheet.get_Range("D4","E8").Locked = false;

            activesheet.Protect(missing, missing, missing, missing, missing, missing, missing,
                                    missing, missing, missing, missing, missing, missing, missing, missing, missing);


        }

When user clicks on the locked cell, excel throws alert message saying cell is locked. Its annoying for user. You may disable displayalerts.

Just use

this.Application.DisplayAlerts = false;

in the ThisAddIn_Startup(object sender, System.EventArgs e) just before declaring var activesheet and do not forget the enable it in again using

private void ThisAddIn_Shutdown(object sender, System.EventArgs e)
        {
            this.Application.DisplayAlerts = true;
        }

This will take care of the annoying alert message.