Object reference not set to an instance of an object. C#

[Markus]

Running a for loop to find the selected check boxes, I ran into this error

Object reference not set to an instance of an object.

This error only occurs if there are no checkboxes selected. Otherwise, it works fine.

The for loop:

for (int i = 0; i < IPArray.Count; ++i)
            {
                DataGridViewRow Row = dataGridView1.Rows[i];
                if ((bool)Row.Cells["Delete"].Value == true)
                {
                    IPArray.RemoveAt(i);
                    NoneSelected = false;
                }
 
            }

The program also stops responding.
The error points to this:

f ((bool)Row.Cells["Delete"].Value == true)

Any ideas because I'm stumped?

[vanc]

It's just because you haven't set all values to that cell. To bypass this issue you should compare its value to "null" before compare it with "true" or "false".

if(aRow.Cells["colDelete"].Value != null && bool.Parse(aRow.Cell["colDelete"].Value) == true)

cheers.