I want to get the sum and also the average of GridView column .If there is any "null" entries in the column then it is not give me the sum.

int i = 0;

int j = 0;

int sum = 0;

try

{

for (i = 0; i < dataGridView1.Rows.Count - 1; i++)

{

for (j = 0; j < dataGridView1.Columns.Count; j++)

{

sum = sum + (Convert.ToInt32(dataGridView1.Rows[i].Cells[j].Value));

}

}

MessageBox.Show("sum"+sum);

}

int j = 0;

int sum = 0;

try

{

for (i = 0; i < dataGridView1.Rows.Count - 1; i++)

{

for (j = 0; j < dataGridView1.Columns.Count; j++)

{

sum = sum + (Convert.ToInt32(dataGridView1.Rows[i].Cells[j].Value));

}

}

MessageBox.Show("sum"+sum);

}

**I want to get average of the column and then place it in the null value cell.**

any body help me