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I got a Datagridview that is empty. The user is able to drag and drop values from a list in to the Datagridview copying the text.. The user is also able to drag and drop values within the Datagrid view moving the text.

But what i also want is for the Rows to drag and drop able (changing the order they appear in).

I manged to do both individually by using the code provided from these 2 answers:

https://stackoverflow.com/a/21133200/10086705 (for cell to cell) How could I Drag and Drop DataGridView Rows under each other? (For dragging rows).

The issue is they both use the same events, my current solution is using a check box to see which one to use. (Checked for row, unchecked for cells) Al tough this works i don't believe this is the most efficient/user friendly way.

This is the code for the dragging of the cells. (Don't mind the try catches they are a temp solution.)

    private Rectangle dragBoxFromMouseDown;
    private object valueFromMouseDown;
    private DataGridViewCell origin;
    private void dataGridView1_MouseMove(object sender, MouseEventArgs e)
    {                    
        if ((e.Button & MouseButtons.Left) == MouseButtons.Left)
        {
            if (dragBoxFromMouseDown != Rectangle.Empty && !dragBoxFromMouseDown.Contains(e.X, e.Y))
            {
                try
                {
                    DragDropEffects dropEffect = dataGridView1.DoDragDrop(valueFromMouseDown, DragDropEffects.Copy);
                }
                catch{}
            }
        }
    }
    private void dataGridView1_MouseDown(object sender, MouseEventArgs e)
    {
        origin = sender as DataGridViewCell;
        var hittestInfo = dataGridView1.HitTest(e.X, e.Y);

        if (hittestInfo.RowIndex != -1 && hittestInfo.ColumnIndex != -1)
        {
            valueFromMouseDown = dataGridView1.Rows[hittestInfo.RowIndex].Cells[hittestInfo.ColumnIndex].Value;
            if (valueFromMouseDown != null)
            {
                origin = dataGridView1.Rows[hittestInfo.RowIndex].Cells[hittestInfo.ColumnIndex] as DataGridViewCell;         
                Size dragSize = SystemInformation.DragSize;
                dragBoxFromMouseDown = new Rectangle(new Point(e.X - (dragSize.Width / 2), e.Y - (dragSize.Height / 2)), dragSize);
            }
        }
        else
        {
            dragBoxFromMouseDown = Rectangle.Empty;
        }
    }
    private void dataGridView1_DragEnter(object sender, DragEventArgs e)
    {
        e.Effect = DragDropEffects.Copy;
    }

    private void dataGridView1_DragDrop(object sender, DragEventArgs e)
    {
        Point clientPoint = dataGridView1.PointToClient(new Point(e.X, e.Y));

        if (e.Effect == DragDropEffects.Copy)
        {
            string cellvalue = e.Data.GetData(typeof(string)) as string;
            var hittest = dataGridView1.HitTest(clientPoint.X, clientPoint.Y);
            if (hittest.ColumnIndex != -1 && hittest.RowIndex != -1)
            {
                try
                {
                    if (dataGridView1[hittest.ColumnIndex, hittest.RowIndex].Value.ToString() != "")
                    {
                        DialogResult dialogResult = MessageBox.Show("Are you sure you want to replace this value?", "!", MessageBoxButtons.YesNo);
                        if (dialogResult == DialogResult.Yes)
                        {
                            dataGridView1[hittest.ColumnIndex, hittest.RowIndex].Value = cellvalue;
                            try{origin.Value = "";}catch{}
                        }
                        else if (dialogResult == DialogResult.No){}
                    }
                }
                catch
                {
                    dataGridView1[hittest.ColumnIndex, hittest.RowIndex].Value = cellvalue;

                    try{origin.Value = "";}catch{}
                }
            }
        }
    }

What i was hoping for is the possibility of an IF statement that checks if a row cell has been selected or if the RowHeader has been selected. In case of the cell it should only move the text from one cell to a other while if the RowHeader is selected it should move the row to a new location (without overwriting any existing row)

1 Answers1

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Have it solved, "if (dataGridView1.SelectedRows.Count == 1)" does the trick. If this is true it will move the row instead of the cell. Got it from the site below: https://www.codeproject.com/Articles/811035/Drag-and-Move-rows-in-DataGridView-Control