What is the process for strong naming an assembly

What is the process for strong naming an assembly ?
What is the purpose of strong naming tool ( sn.exe ) in .NET ?

In .NET, the assembly name usually consists of 4 parts as listed below.
1. Simple Textual Name
2. Version Number (The version number is also divided into 4 parts)
3. Culture
4. Public Key Token

If an assembly contains, all the 4 parts, then the assembly is a strongly named assembly, other wise the assembly is called as a weak named assembly. In general, when you compile any .NET application, the generated assembly by default will have the Simple Textual Name, Version Number and Culture but not the public key token. If you have to sign the assembly with a public key token, you first have to generate the key pair using key generation tool called strong naming tool (sn.exe). The generated key pair will consist of a private and a public key and are written into a key file. Key files have the extension of .snk.

We now have to associate the key file with the project, so that when we compile the project, the generated assembly is signed using the key pair. To do this, In AssemblyInfo.cs file of the project, specify AssemblyKeyFile attribute as shown below.
              [assembly: AssemblyKeyFile("MyKey.snk")]

The last and final step is to build the project which will automatically sign the assembly using the key file. This process generates the strongly named assembly.

In short, there are 3 simple steps to generate a strongly named assembly.
1. Generate the key pair using strong naming tool, SN.exe.

2. Associate the generated Key file to the project using AssemblyKeyFile, which is present in AssemblyInfo.cs file.

3. Build the project.

Once, you have strongly named the assembly, you can copy it to GAC. There are 2 ways to copy an assembly into GAC.
1. Using simple drag and drop : Drag the generated assembly into the GAC folder. Usually the path for GAC is c:\windows\assembly. On some machines this could be c:\winnt\assembly.

2. Use GAC utility : Use GAC Utility tool(gacutil.exe) as shown below in visual studio command prompt.
               gacutil.exe -i C:\MyAssembly.dll (- i stands for install)

Once, you have successfuly copied the assembly into GAC, notice the four parts of the assembly name. The culture column could be empty, indicating that the assembly is language neutral.

Please click here to read few other follow up interview questions related to strong named assemblies.

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  1. The following command creates a new, random key pair and stores it in MyKey.snk

    sn -k MyKey.snk

  2. hi this is really good

  3. Hi please also framework interview questions will be great help

  4. Very Good article

  5. Great explanation!

  6. Thank you very much.

  7. Great way of explaining. Thank you.

  8. Great explaination, thank you very, keep up the good work...!

  9. Hi , good explanation but i hav doubt can u use gac.util in production environment ?
    if not what are the other ways?
    thank u

  10. U are good and ultimate person...good keep it on...

  11. Proud of you...nice articles for anyone preparing for the .NET interviews (be it at any level)
    Keep up the good and noble work
    You can go for writing a book too, as you uses quite a simple and understandable language, which most of the Indians really prefer to read.

  12. Excellent Explanation,Thank you very much

  13. Question... Which folder our generated assemblies after Build would be in before we can copy it to GAC? I created the key and added to Assembly.cs and built the project but not sure where my assembly would be?


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