Object refrence is not set to an instance of an object

Question

I know that here are quite a few similar questions to this one, but some of them are in VB or the answer does not work for my code. So here it is:

 private void dataGridView1_CellClick(object sender, DataGridViewCellEventArgs e)
    {


        if(e.ColumnIndex == 7)
        {

            double cellvalue = new double();
            double totalkcal = new double();
            double totalpret = new double();


            double.TryParse(dataGridView1[e.ColumnIndex - 1, e.RowIndex].Value.ToString(), out cellvalue);
            double.TryParse(dataGridView1[e.ColumnIndex - 3, e.RowIndex].Value.ToString(), out totalkcal);
            double.TryParse(dataGridView1[e.ColumnIndex - 4, e.RowIndex].Value.ToString(), out totalpret);

            textBox5.Text = totalkcal.ToString();


        }
    }

What's wrong with it? I get the error in the title whenever the cell is clicked.

Thanks a lot !

Debug your code. Then you will see what is null. Btw, `dataGridView1[e.ColumnIndex - 1, e.RowIndex]?.Value?.ToString()` may fix *this* error. — György Kőszeg, Apr 04 '16 at 07:47
If it's the last line then your `textBox5` variable is not set (as a double can never be null). — Ian Mercer, Apr 04 '16 at 07:49
Now it works, you was right Ian I had no variable set.Thanks ! — Alex Kayz, Apr 04 '16 at 07:52

score -4 · Answer 1 · answered Apr 04 '16 at 07:46

-4

Give initial values to variables:

double cellvalue = 0;
double totalkcal = 0;
double totalpret = 0;

answered Apr 04 '16 at 07:46

Orkun Bekar

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I did that, however it did not resolve the error. – Alex Kayz Apr 04 '16 at 07:48
when using 'out' you do not need to initiate the ref instances... and double is auto initialized to 0 as it is value instance – Divisadero Apr 04 '16 at 07:48

Object refrence is not set to an instance of an object

1 Answers1