Excel autofill event in C#

Question

I'm writing an Excel add-in using C# and need to be able to tell when users autofill cells.

How can I catch the autofill event?

Answer 1

I found the solution myself after many attempts. The solution is not ideal but it seams to work.

Make sure to handle the worksheet Change event:

displayWorksheet.Change += new Excel.DocEvents_ChangeEventHandler(CellsChange);

the method to handle it should then look like this:

private void CellsChange(Excel.Range Target) 
{
    if ((this.Application.Selection as Excel.Range) != null)
    {
        Excel.Range selectedRange = thisAddIn.Application.Selection as Excel.Range;
        if (selectedRange.Rows.Count > 1)
        {
            //put your code to handle autofill here
        }
    }
}

Answer 2

Here is how I determmine if a single cell has changed or multiples either by pasting a range of cells or by draging values

//Get the currentCell/s changed
        object missing = System.T 
        string currentCell = Target.get_Address(
        missing, missing, Microsoft.Office.Interop.Excel.XlReferenceStyle.xlA1,  missing, missing);


//Split the currentCell variable this aids the logic in getting cell letter and number
         char[] delimiter = new char[] {'$'};
         string[] CellSplit = currentCell.Split(delimiter);


 //try parse the value in position 1 if this is true then a whole sheet has been pasted and needs to be checked
        //usually will be false if 1 cell is changed or multiple by dragging
        Int32 int32Val;
        bool result;
        result = Int32.TryParse(CellSplit.GetValue(1).ToString).Replace":", ""),System.Globalization.NumberStyles.Integer, null, out int32Val);

  //check the length of the array as this will help in determining how the cells have been changed
        int numCellSplit = CellSplit.Length;

  //the result is false if a single cell was changed and the length is 3
        if (CellSplit.Length == 3 && result == false)
        {
          \\your code here
        }
  //the result is true if the whole sheet has been pasted
        if (CellSplit.Length == 3 && result == true)
        {
          \\your code here
        }

  //if the user dragged the data from one cell across others
        if (CellSplit.Length == 5 && result == false)
        {
            //create char arrays to get the Alphabetical letters to use to loop
            char[] FirstLetter = CellSplit.GetValue(1).ToString().ToCharArray();
            char[] SecondLetter = CellSplit.GetValue(3).ToString().ToCharArray();

            int Alphaletter = (char)FirstLetter.GetValue(0);
            int Betaletter = (char)SecondLetter.GetValue(0);
            //Alphabetical letters have an int value so they can be used to loop through the cells
            for (int CellCheck = Alphaletter; CellCheck <= Betaletter; CellCheck++)
            {
                int LoopStart = int.Parse(CellSplit.GetValue(2).ToString().Replace(":", ""));
                int LoopEnd = int.Parse(CellSplit.GetValue(4).ToString());

                for (; LoopStart <= LoopEnd; LoopStart++)
                {

                    //your code here                        
                }   
            }

        }

I hope this helps in some way to determine how the cells have been changed.

Deezos

Answer 3

i want to get excel format cell buttons event in c# add-in to do additional actions after user's click. generally i want catch excel actions when a cell's property is changed like cell's background color or border. i found sheetchange and cellchange events that trigger just for changes of cells content, not cells properties like background color or border or ... earlier thank for your help :)