Object cannot be cast from DBNull to other types for Double Data Type

Question

I am seeing error when there is null value in database for any cell, Object cannot be cast from DBNull to other types. - Asp.net grid view

Answer 1

Then check if it's DBNull or null:

protected string PercentageChange(object client_Price, object second_price)
{
    if(DBNull.Value.Equals(client_Price) || client_Price == null || DBNull.Value.Equals(second_price) || second_price == null)
        return "N/A"; // or whatever

    double price1 = Convert.ToDouble(client_Price);
    double price2 = Convert.ToDouble(second_price);
    double percentagechange = ((price1 - price2) / price2) * 100;
    return percentagechange.ToString();
}