DLL vs EXE in .Net
When programming in .NET, you are given a choice if you want to make an EXE or a DLL. These two both contain executable code but there is a difference between DLL and EXE in how they work. EXE stands for executable, which means that it is an out-process server. If you run the EXE, it would create its own thread and resources will be allocated for it. In contrast, a DLL is an in-process server, which means that you cannot run a DLL file on its own. A running application loads and calls a DLL in order to make use of the code stored in it.
The main purpose of a DLL is so that you can compartmentalize your program. This reduces the complexity and makes it easier to locate problems. If you put all your code into a single executable, it would be quite large and would take quite some time to load. You also get the benefit of reusability if you use DLLs. Say for example that you have a code that exports a file to a new format, if you put that in a DLL, you can use that function on just about any program you are making. If you placed it inside an EXE instead, only that application can use it since the function won’t be visible to others. So for general purpose tasks, using DLLs is very advantageous.
When coding a program in .Net, you need to have an executable since that would be the one that will be executed by the user. The EXE file is essential as it would serve as an entry or starting point for your program. You can then have as many DLLs as you like. Having more than one EXE is not really advisable as they one would not be able to make use of the other.
DLLs are very useful if you program a lot or make rather complicated and large applications. But if you are just making a simple program, using DLLs is not necessary. Keeping the code in a single EXE is simpler and more convenient.
Summary:
- An EXE is an executable while a DLL is an in-process server
- DLLs are reusable while EXEs are not
- You should only have one EXE but you can have multiple DLLs
- An EXE is essential in .NET programming while a DLL isn’t necessarily essential