If u are Entering Values in GridView Cells.
Handle Datagridview1_CellValueChanged Event
Exa:
private void dgrid_CellValueChanged(object sender, DataGridViewCellEventArgs e)
{
if(e.RowIndex>=0)
{
if(!string.IsnullOrEmpty(dgrid.Rows[e.RowIndex].Cells["quantity"].Value.ToString()) && !string.IsnullOrEmpty(dgrid.Rows[e.RowIndex].Cells["Price"].Value.ToString())
{
dgrid.Rows[e.RowIndex].Cells["commonPrice"].Value = Convert.ToDouble(dgrid.Rows[e.RowIndex].Cells["quantity"].Value) *
Convert.ToDouble(dgrid.Rows[e.RowIndex].Cells["Price"].Value)
}
}
}
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