programming-for-dummies

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“Curly Bracket” Languages
Type safe
A second advantage of C# is type-safe language. Basically, if a C# program
stores data, such as a whole number (such as 3 or 49, but not 5.48), the C#
compiler checks to make sure no other part of the program accidentally
changes that whole number into a decimal.
With languages that aren’t type-safe, the compiler lets a program change data
types, such as storing a decimal or negative number where the program
expects a whole number. Obviously, if your program is expecting a whole
number but instead receives a decimal number, the program may get confused
and crash.
.NET compatibility
Because Microsoft invented C#, they also invented a special program — the
.NET framework. The idea behind the .NET framework is that instead of compiling
a C# program into machine language, you compile a C# program into p-
code, which is similar to the bytecode intermediate file format of Java.
Theoretically, you can run a C# program on any computer that has the .NET
framework on it. Realistically, the only computers that have the .NET framework
are computers running the Windows operating system. So if you write
a C# program, you’re essentially locked into writing programs that run only
under Windows. A band of hardy programmers are trying to rewrite the .NET
framework to run under the Linux operating system, but this doesn’t have
the official blessing of Microsoft, so C# programs are guaranteed to work
only on Windows.
The .NET framework allows you to both
✦ Run C# programs on any computer with the .NET framework.
✦ Write programs in multiple languages that all link together through
the .NET framework, as shown in Figure 3-5.
By letting you write a program with different languages, the .NET framework
lets you use each language’s strengths without being forced to put up with
that language’s weaknesses.
The only programming languages you can use with the .NET framework are
languages specifically designed to work with the .NET framework. So if you
want to write a program using a combination of C# and BASIC, you have to
find a BASIC compiler that works with the .NET framework, such as
Microsoft’s own Visual Basic language.
A final advantage of the .NET framework is that it lets you use event-driven
programming to create your user interface and then write event handlers in
any .NET language, such as C#.