Type Library Importer : tlbImp



This tool is used to convert the type library definitons found in COM

components to .NET assembly. This tool works on the entire type



library at the same time and hence you cannot use this tool to generate type

information for a particular type found in the COM



Component. The assemblies that are produced by this tool can be easily

strong named by using the /keyfile or /keycontainer options.



Lets checkout the tlbimp tool options :-



1) Go to the VS.Net command prompt.



2) type tlbimp /? and all the option will be displayed. I have listed a few

imp ones here.



/out:FileName File name of assembly to be produced



/namespace:Namespace Namespace of the assembly to be produced



/publickey:FileName File containing strong name public key



/keyfile:FileName File containing strong name key pair



/keycontainer:FileName Key container holding strong name key pair



/delaysign Force strong name delay signing



/nologo Prevents TlbImp from displaying logo



/primary Produce a primary interop assembly



/asmversion:Version Version number of the assembly to be produced :- The

assembly version must be specified as:Major.Minor.Build.Revision.



/reference:FileName File name of assembly to use to resolve references :-

Multiple reference assemblies can be specified by using the /reference

option multiple times.



Lets now import a COM type library and check out some of these features.



3) Create a new Windows Application.



4) To view the list of COM components on your machine right click on the

project and select add reference. In the Add refernce dialog select the COM

tab.This tab will display all the COM components on your machine.



5) I have selected to import the microsoft rich text control i.e.

RICHTX32.ocx.This control will be placed in C:/winnt/system32.



6) Copy the control to your project folder and excute the below command to

generate the assembly.



tlbimp richtx32.ocx



7) You should get a message saying : "Type library imported to

RichTextLib.dll".



This dll that we have created can be strong named by using /keyfile: or

/keycontainer or /public key option.



8) Generate a strong name key to strong name the assembly with



sn -k MyKey.snk.



9) Regenerate your assembly with a strong name as follows :



tlbimp richtx32.ocx /keyfile:MyKey.snk



10) To change the name of the assembly produced by the tlbimp use the /out:

option



tlbimp richtx32.ocx /out:Namratha.dll



11)Let us now copt another file called "MSACC9.OLB". You find this file on

any machine with MSOffice in the "<drive>:\Program Files\Microsoft

Office\Office" folder.



12) Now crearte an interop assembly for this Component with the below

command



tlbimp msacc9.olb



13) You will notice that it creates the following 5 assemblies



ADODB.dll



DAO.dll



Office.dll



VBIDE.dll



Along with the main one "Access.dll"



13) Here this assembly is internally referencing the first four assemblies

and hence it has created assemblies for the same also.



14) Microsoft does provide us with the primary interop for ADODB.dll ...

hence if you want refer to the primary interop assembly and avoid generation

of a new interop assembly use the /reference option.



15) You will find all the primary interop assemblies in "<drive>:\Program

Files\Microsoft.NET\Primary Interop Assemblies" folder where drive is where

..NET is installed. You will see a primary interop for ADODB also.



16) You can use the following command to refer to the existing Primary

Interop Assembly (PIA .... is not Pakistan International Airlines ..just

kidding ) adodb.dll.



tlbimp msacc9.olb /reference:"C:\Program Files\Microsoft.NET\PrimaryInterop

Assemblies\adodb.dll" /verbose



17) The /verbose option will show you all the details while creating the

interop assembly.



18) If want your assembly to only refer a set of assemblies that is you have

all its referneced assemblies you can give multiple references while

creating the Interop Assembly and for tlbimp to use only those assemblies

you can specify the /strictref option. By doing this tldimp will only and

only refer to those assembly files which you have metioned with /reference

option.



19) Well If you want to create a PIA for your own COM component then use the

/primary option while creating the assembly.



20) Use the /asmversion option to maintain version of your PIA's.



21) Now we are ready to use these assemblies in our project and inanswering

our interview questions .







-- Please post your queries and comments for my articles in the usergroup

for the benefit of all. I hope this step from my end is helpful to all of

us.



Regards,



Namratha (Nasha)

Excellent Article. I was just looking for this.

I am trying to call a DCOM object in webservice. It is not working.



I hope it works now.



Thanks

Dev