1. The code-behind allows you easier to maintain the code when it comes to
large websites.
2. You have the freedom of choosing from multiple
languages (C#, VB.NET, C++, etc.)
3. SQL Server is also very fast, secure, and it can
store extremely large amounts of data; actually,
there’s no limit;
4. With ASP.NET you get the whole .NET Class Library and the thousands of
third party components as well. There are definitely much more third party
components out there for .NET than for PHP.
5. The Visual Studio .NET IDE. makes coding much, much easier. It can
highlight syntax, let you know when the wrong stuff is commented, do
command completion, and just plain help you organize better. Visual Studio
has a really nice debugger.

6. The Compiled Code (vs. PHP
Interpreted Code) – .NET compiles
code, such as C#, into what its
creators have termed MSIL
(Microsoft Intermediate Language).
7. In ASP.NET it’s easy to use threads and build asynchronous handlers in
your server-side web code.
8. ASP.NET developers are paid better because of Its better future &
advantages over other Languages in terms of different issues.