Unknown Name error when accessing .NET dll

[ljfrench]

Hello, Macrovision Community! I need your help on a very frustrating issue.

I need to call a DLL to validate a license key during my installation. I'm writing a TEST installscript to prove the concept.

I am able to load the dll successfully with DotNetCoCreateObject but am receiving an 'Unknown Name' error with an error number of -2147352570 when attempting to access a public function.

My support files make it into the specified directory successfully. I've also written a C# test project to call the dll and pass a key and it works just fine.

Code snippets below:

Visual Studio AssemblyInfo.cs file:
[CODE]using System.Reflection;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;

//
// General Information about an assembly is controlled through the following
// set of attributes. Change these attribute values to modify the information
// associated with an assembly.
//
[assembly: AssemblyTitle("")]
[assembly: AssemblyDescription("")]
[assembly: AssemblyConfiguration("")]
[assembly: AssemblyCompany("")]
[assembly: AssemblyProduct("")]
[assembly: AssemblyCopyright("")]
[assembly: AssemblyTrademark("")]
[assembly: AssemblyCulture("")]
[assembly: ComVisible(true)]
ETC...[/CODE]

Visual Studio Validation.cs file:

using System;
using System.Collections;
using System.Text.RegularExpressions;
using ServerIdentifier;

namespace ServerValidation
{
	
    /// 

	/// Summary description for Validation.
	/// 
	public class Validation
	{
        //
		// Member variables and constants
		private static bool m_blnUseMachineIdentifier = true;
        
		#region Public Interface 

		public static bool ValidateKey(string strKey)
		{
			if(ValidateMachineKey(strKey))
			{
				return true;
			}
			else
			{
				if(ValidateTimeKey(strKey))
				{
					return true;
				}
				else
				{
					return false;
				}
			}
		}
ETC...

Installscript Code:

#define DLL_NAME "ServerValidation.dll" 
// Include Ifx.h for built-in InstallScript function prototypes.
#include "Ifx.h"
// Prototype MydllReturn in Mydll.dll.
//prototype BOOL ServerValidation.ValidateKey (BYVAL STRING);
//prototype BOOL ServerValidation.VerifyLoading ();
export prototype ExFn_UseDLL(HWND);

function ExFn_UseDLL(hMSI)
	STRING svString;
	INT nValue;
	POINTER psvString;
	NUMBER nResult;
	BOOL bValidKey;      
	STRING szMSISUPPORTDIR;
	STRING szPathCompletDll;
	NUMBER nTemp;  
	OBJECT objValidateKey;
begin                
	//Get the path to the MSI SUPPORTDIR
	MsiGetProperty(hMSI, "SUPPORTDIR", szMSISUPPORTDIR, nResult);
	szPathCompletDll = szMSISUPPORTDIR ^ DLL_NAME;
	
	// Load the .dll file into memory.
	set objValidateKey = DotNetCoCreateObject( szPathCompletDll, "ServerValidation.Validation", "");
	
	// bValidKey controls the following while loop.
	bValidKey = FALSE;
	
	// Loop while bValidKey is FALSE.
	while (bValidKey = FALSE)      
		      
		try 
			// Call ValidateKey .
			bValidKey = objValidateKey.ValidateKey("0000-1111-2222-3333");
		catch
		    /* Exception handler. */
			//nTemp = Err.Number;                  
			//svString = Err.Description;
			/* Handle the exception based on its cause. */
			SprintfBox (INFORMATION, "Error","Error occured: %i\n\n%s\n\n%s", 
				Err.Number, Err.Description, Err.LastDllError);  
			abort;
		endcatch;
		
		// Display the string to observe how it was altered by MydllReturn.
		if (bValidKey) then
			MessageBox ("Valid Key", INFORMATION);
		else
			MessageBox ("Invalid Key", INFORMATION);
		endif;
		
	endwhile;
	
end;

Thank you for your help!
Len

[RobertDickau]

One quick thing to test: in your InstallScript, does szPathCompletDll have the correct value? Your MsiGetProperty call to get SUPPORTDIR might fail if you haven't set the buffer-size variable nResult to a large enough value (say, MAX_PATH+1) before calling MsiGetProperty...

[ljfrench]

RobertDickau wrote:
One quick thing to test: in your InstallScript, does szPathCompletDll have the correct value? Your MsiGetProperty call to get SUPPORTDIR might fail if you haven't set the buffer-size variable nResult to a large enough value (say, MAX_PATH+1) before calling MsiGetProperty...

Robert,
I believe I have the correct value. I added a SprintfBox statement to check. szPathCompletDll is correct. I can leave the installer open and verify the DLL's presence in the temp folder.

I also placed the DLL in a static location and directed the installer to use that. Same problem.

Code snippet of my SprintfBox statement:

//Get the path to the MSI SUPPORTDIR
	MsiGetProperty(hMSI, "SUPPORTDIR", szMSISUPPORTDIR, nResult);
	SprintfBox(INFORMATION, "nResult", "%s\n\n%s\n\n%d\n\n%d", szMSISUPPORTDIR ^ DLL_NAME, szMSISUPPORTDIR, nResult, StrLength(szMSISUPPORTDIR));

[MichaelU]

Might it help to remove static from public static bool ValidateKey(string strKey)? It strikes me as odd that one would try to call a static method from an object instance, COM or otherwise.

[ljfrench]

MichaelU wrote:
Might it help to remove static from public static bool ValidateKey(string strKey)? It strikes me as odd that one would try to call a static method from an object instance, COM or otherwise.

Right on, Michael! I thought about it after your post and I realized that the class methods would not be available to my instantiation of the class into my object in the installer.

I added a non-static method to the class and called the validation method from there. Works like a charm!

Quite a 'duh' moment.

Thank you again!

Len

😄 😄