CRM 2011 Plugin - Check if OptionSet is not empty - plugins

Question

I am writing a plugin where I check if a particular value of a field, an Option Set is equal to a specific value and if so, then I do certain actions.
Now, within the plugin C# code, how can I check that the Option Set field is not null - i.e., is set to the Default Value?
What I did (clearly, that is wrong) because, it never went past the Null check statement. And, if I did not have the check, then I get this error message
Error:
Unexpected exception from plug-in (Execute): CRM.AppStateHandler.Plugins.PostApplicationCreate: System.NullReferenceException: Object reference not set to an instance of an object.
Code:
application applicationEntity = entity.ToEntity<new_application>();
if (new_applicationEntity.new_Applicationstatus != null)
{
var applicationStatus = applicationEntity.new_Applicationstatus.Value;
if (applicationStatus == CRMConstants.EntityApplication.Attributes.ApplicationStatusOptions.Applying)
{
//my logic
}
}
File constants.cs has the following
class CRMConstants
{
public struct EntityApplication
{
public struct Attributes
{
public struct ApplicationStatusOptions
{
// More before this
public const int Applying = 100000006;
// More to come
}
}
}

Answer 1

I think SergeyS has your fix, but I'll add some other (hopefully) helpful comments.
Don't custom create structs for your Option Set Values. Use the CrmSrvcUtil to create enums for you automatically.
I get annoyed with having to check for OptionSetValues being null or not, so I use these extension methods to make my life easier:
/// <summary>
/// Returns the value of the OptionSetValue, or int.MinValue if it is null
/// </summary>
/// <param name="osv"></param>
/// <param name="value"></param>
/// <returns></returns>
public static int GetValueOrDefault(this OptionSetValue osv)
{
return GetValueOrDefault(osv, int.MinValue);
}
/// <summary>
/// Returns the value of the OptionSetValue, or int.MinValue if it is null
/// </summary>
/// <param name="osv"></param>
/// <param name="value"></param>
/// <returns></returns>
public static int GetValueOrDefault(this OptionSetValue osv, int defaultValue)
{
if (osv == null)
{
return defaultValue;
}
else
{
return osv.Value;
}
}
/// <summary>
/// Allows for Null safe Equals Comparison for more concise code. ie.
/// if(contact.GenderCode.NullSafeEquals(1))
/// vs.
/// if(contact.GenderCode != null && contact.gendercode.Value == 1)
/// </summary>
/// <param name="osv"></param>
/// <param name="value"></param>
/// <returns></returns>
public static bool NullSafeEquals(this OptionSetValue osv, int value)
{
if (osv == null)
{
return false;
}
else
{
return osv.Value == value;
}
}
/// <summary>
/// Allows for Null safe Equals Comparison for more concise code. ie.
/// if(contact.GenderCode.NullSafeEquals(new OptionSet(1)))
/// vs.
/// if(contact.GenderCode != null && contact.gendercode.Value == new OptionSet(1))
/// </summary>
/// <param name="osv"></param>
/// <param name="value"></param>
/// <returns></returns>
public static bool NullSafeEquals(this OptionSetValue osv, OptionSetValue value)
{
if (osv == null)
{
return osv == value;
}
else
{
return osv.Equals(value);
}
}
There are two methods each with an overload:
GetValueOrDefault - This is equivalent to the Nullable.GetValueOrDefault(). The one difference is rather than defaulting to 0, I default to int.MinValue to make sure I don't accidentally match on a 0 optionset value. The Overload allows you to specify the default value if you'd like.
NullSafeEquals - This is the one you'd be using in your code to not have to check for null
application applicationEntity = entity.ToEntity<new_application>();
if (applicationEntity.new_Applicationstatus.NullSafeEquals(CRMConstants.EntityApplication.Attributes.ApplicationStatusOptions.Applying))
{
//my logic
}

Answer 2

You are checking:
if (new_applicationEntity.new_Applicationstatus != null)
but you need to check:
if (applicationEntity.new_Applicationstatus != null)