Reflection

Question

I am using reflection to get load an assembly. I donot know how to get the properties of the object using reflection. I want to know how to get the values of the properties in the object. I have attached my code if any one could check what is missing I would be thankful. string strPath = GetInstalledPath(); asm = Assembly.LoadFrom (strPath); PublishType = asm.GetType(ControlLicenseService.LicenseInfoClient); Object theObj = Activator.CreateInstance(PublishType); // Array with Two members for passing the Parameter for Initialize method. Type[] paramTypes = new Type[2]; paramTypes[0]= Type.GetType(System.String); paramTypes[1]= Type.GetType(System.Int32); // Get method info for Initialize( ) MethodInfo InitializeInfo = PublishType.GetMethod(InitializeparamTypes); // Fill the array with the actual parameters Object[] parameters = new Object[2]; parameters[0] = sk26901CODA904O; parameters[1] = 10300; Object returnVal = InitializeInfo.Invoke(theObjparameters); pi = PublishType.GetProperty(UsersCount); string valu = pi.GetValue(theObjnull).ToString(); MessageBox.Show(valu);

misterraj · Answer

nothing worked properly.

shimtanny · Answer

Hi As you already had done. Object[] parameters = new Object[2]; parameters[0] = sk26901CODA904O; parameters[1] = 10300; InitializeInfo.Invoke(theObjparameters); (I mean without parameter type on getting the method info). Cheers Simon

misterraj · Answer

Hi So how do I pass the parameters to the method? Can you elaborate pls. Venkat.

shimtanny · Answer

Hi I had no problem to do something similar like the code above. There are some differences: 1. using Object theObj = asm.CreateInstance(ControlLicenseService.LicenseInfoClient); 2. using MethodInfo InitializeInfo = PublishType.GetMethod(Initialize); (Instantiating types found with reflection uses some remoting some asynchronous calls... therefore i could imagine that an exception was thrown but not visible beause on a different callstack.) Maybe it helps. Cheers Simon

misterraj · Answer

Hi Simon Thanks for your immediate reply I feel that the method itself is not invoked properly. The initialize method may inturn have lot of methods called internally. This is the piece of code in Early Binding and works as expected. --------------------------------------------------------------------------- using ControlLicenseService LicenseInfoClient lic =new ControlLicenseService LicenseInfoClient(); lic.Initialize(sk26901CODA904O10300); if (lic.IsSuccess ) { MessageBox.Show(Success); } else MessageBox.Show(Failure); This is my code in Late binding: ------------------------------------ Assembly asm = null; Type PublishType = null; try { string strPath = GetInstalledPath(); asm = Assembly.LoadFrom (c:\somefile.dll); PublishType = asm.GetType(ControlLicenseService.LicenseInfoClient); Object theObj = Activator.CreateInstance(PublishType); // Array with Two members for passing the Parameter for Initialize method. Type[] paramTypes = new Type[2]; paramTypes[0]= Type.GetType(System.String); paramTypes[1]= Type.GetType(System.Int32); // Get method info for Initialize( ) MethodInfo InitializeInfo = PublishType.GetMethod(InitializeparamTypes); // Fill the array with the actual parameters Object[] parameters = new Object[2]; parameters[0] = sk26901CODA904O; parameters[1] = 10300; InitializeInfo.Invoke(theObjparameters); PropertyInfo pi = PublishType.GetProperty(IsSuccess); string valu = pi.GetValue(theObjnull).ToString(); MessageBox.Show(valu); } Does there are any exceptions in reflections? What I found thru debugging was the parameters are setting properly n the late binding but the method is not invoked properly or it fails in the method. Any clue where the error is?. I hope I can get the value of the properties once the method is invoked properly.

shimtanny · Answer

Hi I've made a small sample which loads a assembly instantiate a type of it and sets/gets a property: // Code in the main app. Assembly a = Assembly.LoadFrom(Library.dll); Object o = a.CreateInstance(Library.Class1); Type t = o.GetType(); PropertyInfo pi = t.GetProperty(Value); pi.SetValue(o A Value null); Object value = pi.GetValue(o null); // Code in the client app. containing the type to instantiate. namespace Library { public class Class1 { private string value = string.Empty; public Class1() {} public Class1(string value) { this.value = value; } public string Value { get { return this.value; } set { this.value = value; } } } } I cannot fully follow your example because there are several small mistakes. Try to debug... - is the assembly correctly loaded? - are there any exceptions maybe not seen because on another callstack? - does the property info contain any information? Cheers Simon