Calculation in Data Grid

Question

// Please solve this problem Object cannot be cast from DBNull to other types.

private void dataGridView1_CellEndEdit(object sender, DataGridViewCellEventArgs e)
        {
            if (e.ColumnIndex == 0 || e.ColumnIndex == 1)
            {
                int cell1 = Convert.ToInt32(dataGridView1.CurrentRow.Cells[0].Value);
                int cell2 = Convert.ToInt32(dataGridView1.CurrentRow.Cells[1].Value);
                if (cell1.ToString() != "" && cell2.ToString() != "")
                {
                    dataGridView1.CurrentRow.Cells[2].Value = cell1 + cell2;
                }
            }
        }
// I am doing this. but it is showing below error...

Object cannot be cast from DBNull to other types.

so please try to solve.

Suthish Nair · Answer

try i nt cell1 = 0; if (!(IsDbNull( dataGridView1.CurrentRow.Cells[0].Value )) { cell1 = Convert.ToInt32(dataGridView1.CurrentRow.Cells[0].Value); }

Sam Hobbs · Answer

You need to learn how to use the debugger. Look in this web site for articles about debugging. Learn how to set a breakpoint. Then tell us specifically what line is getting the error and what field is null. It will help you many times in the future if you know how to do these things.

Wil Youmans · Answer

C#: I think it would be like: if(dataGridView1.CurrentRow.Cells[0].Value is System.DBNull) // then assign some arbitrary //value else int cell1 = Convert.ToInt32(dataGridView1.CurrentRow.Cells[0].Value);

Sam Hobbs · Answer

You can do as Wil says to determine more precisely what is happening. You can do that without changing the source code. I suggest that you add code to ensure that items are not null. I am not sure what you need to check for nulls but after debugging you will know what to check to at least solve that problem. I also suggest using Int32.TryParse to convert the numbers instead of Convert.ToInt32.

sudhir kumar · Answer

can you please send me a new code for calculation in data grid.I am trying but it is still showing error.. so please send me an example for data grid calculation if possible...

Wil Youmans · Answer

Can you use your debugger to set a break point by 'int cell1' and check the values being assigned. Either Cells[0] or Cells[1] value is DBNull meaning there is no real data there and when it is attempted to be converted to an int it throws an error.