Cannot implicitly convert type 'decimal?' to 'decimal'.

Question

sdr is my sqldatareader and I want to check that the curPrice value which is of type decimal is null.

inrec.curPrice = sdr.IsDBNull(7) ? (decimal?)null : sdr.GetDecimal(7);

This is the error message I am getting:

Cannot implicitly convert type 'decimal?' to 'decimal'. An explicit conversion exists (are you missing a cast?)

Where am I going wrong, please someone tell me.

Speedway

Answer 1

either convert curPrice to nullable, or use .Value property of nullable types.

If curPrice is a property of a class then

public decimal? curPrice
{
   get;
   set;
}

Ptolemaeus

Answer 2

decimal? indicates that it's a nullable decimal; you have to use the Value property to get the actual value (if it exists, determined via HasValue).

I'm assuming curPrice is a non-nullable decimal, in which case you need to also figure out a better value to return than null from the true side of your ternary operator.

Tailspin

I'm confused. Would you happen to have code samples to explain what you mean..real sorry this is very new to me. – Speedway

Answer 3

inrec.curPrice = sdr.GetValueOrDefault(0m)

Since the left side (Price) does not allow for null then you cannot set its value to something that could be null. Therefore, use .GetValueOrDefault(decimal defaultValue) to return a default value when null.

Bumble

Answer 4

How about converting the decmial? type to decimal ?

You have to have what value you like inrec.curPrice to have when sdr.GetDecmial(7) is null.

inrec.curPrice = sdr.GetDecimal(7) ?? 0M;

I assumed that you would want to use 0 if what's returned was null. If not change 0M to some other decimal value.

--- Update after replay

How about inrec.curPrice = sdr.IsDBNull(7) ? 0M : sdr.GetDecimal(7); ?

Heelandtoe

When I do that, I get this error: Error 7 Operator '??' cannot be applied to operands of type 'decimal' and 'decimal' – Speedway

Ah.. I just looked up .GetDecimal() in MDSN, It returns a decimal and not decimal? so my answer was nonsense. Sorry about that. – Heelandtoe