Cheat Sheet
C# 2008 For Dummies
C# 2008 is an awesome programming language. Discover the operators you need to perform your functions and how to declare and use variables like integers, floating points, and others. Also take a look at how to control program flow in C# 2008.
Operators in C# 2008
In order to perform operations in C# 2008, you need, well…operators. The following chart shows you these operators. These symbols determine which operations to carry out in an expression:
| Precedence | Operators | Cardinality | Associativity |
|---|---|---|---|
| High | () [] . new typeof | Unary | Left to right |
| * | ! ~ + - ++ -- (cast) | Unary | Left to right |
| * | * / % | Binary | Left to right |
| * | + - | Binary | Left to right |
| * | < <= > >= is as | Binary | Left to right |
| * | == != | Binary | Left to right |
| * | & | Binary | Left to right |
| * | ^ | Binary | Left to right |
| * | | | Binary | Left to right |
| * | && | Binary | Left to right |
| * | || | Binary | Left to right |
| * | ?: | Ternary | Right to left |
| Low | = *= /= %= += -= &= ^= |= <<= >>= | Binary | Right to left |
C# 2008 Integer Variable Types
Each variable has a fixed type in C#, and integer (int) variable types are limited to whole numbers. C# has several other integer variable types, shown in this chart:
| Type | Size (bytes) | Range | In Use |
|---|---|---|---|
| sbyte | 1 | -128 to 127 | sbyte sb = -12; |
| byte | 1 | 0 to 255 | byte b = 12; |
| short | 2 | -32,768 to 32,767 | short sn = -123; |
| ushort | 2 | 0 to 65,535 | ushort usn = 123; |
| int | 4 | -2,147,483,648 to 2,147,483,647 | int n = 123; |
| uint | 4 | 0 to 4,294,967,295 | uint un = 123U; |
| long | 8 | -9,223,372,036,854,775,808 to 9,223,372,036,854,775,807 - “a whole lot” | long l = 123L; |
| ulong | 8 | 0 to 18,446,744,073,709,551,615 | long ul = 123UL; |
C# 2008 Floating Point Variable Types
C# distinguishes real numbers, which come in two styles: floating point and decimal. Floating point is the most common and floating-point variables are assigned. This chart describes the two floating-point variables in C#:
| Type | Size (bytes) | Range | Accuracy | In Use |
|---|---|---|---|---|
| float | 8 | 1.5 * 10-45 to 3.4 * 1038 | 6-7 digits | float f = 1.2F; |
| double | 16 | 5.0 * 10-324 to 1.7*10308 | 15-16 digits | double d = 1.2; |
Controlling Program Flow in C# 2008
C#, like most programming languages, can make decisions. You can create a C# program that reads your data and automatically performs the tasks you need. Depending on the attributes of the information it's processing, a C# program can skip sections of code, run other C# programs (subroutines), and repeat sections of code just as many times as necessary to process the data. If you've used other programming languages, these powerful functions will be familiar friends:
