object' does not contain a definition for 'CreateInstance' ?

Barkha Shukla

AssemblyName assembly = new AssemblyName();
var myAssembly = Assembly.Load(@"D:\MyLabBeDevelopmet1.0\Test\bin\Debug\MongoDBLogger.dll");
EventNotifier.IEventNotifier eventNotifier = myAssembly.CreateInstance("MongoDBLogger.Logger") as EventNotifier.IEventNotifier;
eventNotifier.Log(FinalXML);

9 Replies

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Barkha Shukla11y ago
thanks
Vulpes11y ago
Well, after making something up for the interface:

namespace EventNotifier
{
interface IEventNotifier
{
void Log(string s);
}
}

I tried the code myself and it compiled fine.

So the only other reason I can think of for this error is that you're not using the System.Reflection.Assembly class in the .NET framework but a 'custom' Assembly class which:

1. May or may not inherit from the former.

2. Has a Load method which returns an object rather than an Assembly.

Am I close here?
Barkha Shukla11y ago
I comment eventnotifier.log but didn't work
Barkha Shukla11y ago
I comment eventnotifier.log but didn't work
Vulpes11y ago
Sorry, just realized that this is a compile time rather than a run time error so it can't be a problem within one of the .NET framework methods.

If you comment out the last line, does the error still occur?

eventNotifier.Log(FinalXML);
Barkha Shukla11y ago
'object' does not contain a definition for 'CreateInstance' and no extension method 'CreateInstance' accepting a first argument of type 'object' could be found (are you missing a using directive or an assembly reference?)
Vulpes11y ago
It's difficult to make sense of this error because the Assembly.Load method returns an Assembly object. Consequently, myAssembly must be of type Assembly rather than System.Object and the Assembly class definitely does have a CreateInstance method.

I think the error must therefore be bubbling up from inside one of the methods you're calling.

What's the 'full' error message here?
Barkha Shukla11y ago
I have tried but still same error
11y ago
Hi,
Can you please try the below code?

AssemblyName assembly = new AssemblyName();
var myAssembly = Assembly.Load(@"D:\MyLabBeDevelopmet1.0\Test\bin\Debug\MongoDBLogger.dll");
var eventNotifierObj = myAssembly.CreateInstance("MongoDBLogger.Logger");
EventNotifier.IEventNotifier eventNotifier = eventNotifierObj as EventNotifier.IEventNotifier;
eventNotifier.Log(FinalXML);