change expression return type

[Dilbert]

I am using Expression Editor control which uses Finances object which has nullable double fields (values): Debit (10), DebitYTD (100), Credit (20) and CreditYTD (200). In the formula, I want to do something like: Debit - Credit + DebitYTD - CreditYTD and this works fine and returns LinqExpression<Func<Finances, double?>> type. The problem is when I try to do something like 0.045 * (Debit) which returns a LinqExpression<Func<Finances, decimal>> type. How do I handle two different return types? Can I make expression control to always return LinqExpression<Func<Finances, double?>> type?

Update: This is a blocking issue for us, so I would request the telerik team to provide a solution or an approach on how to handle this scenario. Thanks!

[Jarred Froman]

We are experiencing a similar problem as well.  Is there any update on this?

Thanks

[Dimitrina]

Hello,

For double constants you should use the exponential value: for example 0.0E+2. This should lead to result of type double.

All the best,
Didie
the Telerik team

[Jarred Froman]

Requiring the users to enter numbers in this way does not seem feasible.  Can a property be added to the control casting / requiring valid output type(s)?  This would make the control even more powerful by adding in an extra level of validation.

Thanks!

[Dimitrina]

Hello,

 You can convert the expression that is returned from the editor. For example if your returned expression is 'decimalExpr', then you can convert it with a code similar to this one:

var newBody = Expression.Convert(decimalExpr.Body, typeof(double?));
var expr2 = Expression.Lambda(newBody, decimalExpr.Parameters) as Expression<Func<Finances, double?>>;
var func = expr2.Compile();

I hope that this is helpful.

All the best,
Didie
the Telerik team