if (Session[" currentOrderId"] != string.Empty)

Question

User-605499000 posted

Possible unintended reference comparison to get a value comparison  Cast the left hands id to type "string"  error.

Below is the code.  I see that a lot of people are getting this error but still could not fix.

bool ret = payPalCaller.DoCheckoutPayment(finalPaymentAmount, token, PayerID, ref decoder, ref retMsg);
if (ret)
{
// Retrieve PayPal confirmation value.
string PaymentConfirmation = decoder["PAYMENTINFO_0_TRANSACTIONID"].ToString();
TransactionId.Text = PaymentConfirmation;

ProductContext _db = new ProductContext();
// Get the current order id.
int currentOrderId = -1;
if (Session[" currentOrderId"] != string.Empty)
{
currentOrderId = Convert.ToInt32(Session["currentOrderID"]);   ( here is where the error is)
}
Order myCurrentOrder;
if (currentOrderId >= 0)
{

thanks

Jen

Answer 1

User475983607 posted

This syntax is incorrect.  Session returns an object and therefore you must cast the Session variable to the correct type.

if (Session[" currentOrderId"] != string.Empty)

For example...

if (Session["currentOrderId"] != null && (string)Session["currentOrderId"] != string.Empty)

The ASP Session support documents explain the how to use Session.

https://msdn.microsoft.com/en-us/library/ms178581.aspx?f=255&MSPPError=-2147217396

Answer 2

User-605499000 posted

Thank you so much that worked beautifully.  I was close thinking that I needed null but nothing I did worked. I am not a programmer and trying to redo my business site that was built in 2009.  I chose Wingtops as a way to do it but have run into many problems.

Thank you so much for your help.  Everyone on this forum is excellent and has helped me so much.

Jen