Report Datetime Parameter value set to current datetime on Null value

Hi Sergi,
Although you have provided a workaround solution. This is not a good way at all. Everytime, I create a new report I have to remember to do this and for all the parameters that I have a datetime type.
I was very disappointed to hear that this is "by design" behavior!
When many of your datetime controls does not behavior this way and even in report when data is coming from the datatable or linq datasource.
Why do you code it different for the report parameter?
Many members of my Development team are not happy with your components and I am starting to loose faith in your product :(
Vinh,

Hi Vinh,
Thank you for your feedback. We understand your frustration. I am afraid the current behavior is implemented due to .NET Framework restrictions. The DateTime class does not support null values. If you try to assign a null value to a DateTime class instance, you will get the "Cannot convert null to 'System.DateTime' because it is a value type" compiler error. So, I am afraid we cannot change this default behavior. To avoid this problem, you can use the nullable DateTime? class for parameters. This way, you will be able to assign null values for DateTime parameters. Please refer to the code below:

C#
...  
            Parameter parameter = new Parameter();  
            parameter.Type = typeof(DateTime?);  
            parameter.Name = "parameter";  
            parameter.Value = null;  
            this.Parameters.Add(parameter);  
...  

We look forward to your feedback once you have had the opportunity to try this approach.
Thanks,
Sergi

Sound like a workable solution.
Let me ask dump question, how do I pass/bind this parameter to the report control?
I normally link the parameter to my XRLabel control at design time and only assign value to the parameter at runtime. With this dynamic creating of parameter how do I bind it the control?
Thanks,
Vinh,

Hi Vinh,
Thank you for your feedback. You can bind XRControl to a parameter created at runtime via MailMerge. Please refer to the Embedded Fields (Mail Merge) article, illustrating this approach in action. Attached is a sample project, showing how this can be done.
Thanks,
Sergi

Just for anybody else when you change the report's designers datatype for you parameter to typeof(DateTime?) the parameter is then from that time forward null-able although the DevExpress parameter editor does not a provide an option to specify that it's null-able they do re-generate the property type as System.Nullable<DateTime> which is exactly the behaviour I required.
Hope this helps.
Cheers