Chapter 2

Chapter 2

Working with Variables, Operators, and Expressions

After completing this chapter, you will be able to:

• Understand statements, identifiers, and keywords.

• Use variables to store information.

• Work with primitive data types.

• Use arithmetic operators such as the plus sign (+) and the minus sign (–).

• Increment and decrement variables.

In Chapter 1, “Welcome to C# 2005,” you learned how to use the Microsoft Visual Studio 2005 programming environment to build and run a console program and a Windows Forms application. In this chapter, you'll be introduced to the elements of Microsoft Visual C# 2005 syntax and semantics, including statements, keywords, and identifiers. You'll study the primitive types that are built into the C# 2005 language and the characteristics of the values that each type holds. You'll also see how to declare and use local variables (variables that exist only within a function or other small section of code), learn about the arithmetic operators that C# 2005 provides, learn how to use operators to manipulate values, and learn how to control expressions containing two or more operators.

the following is :

Chapter 2 Quick Reference

To	Do this
Declare a variable	Write the name of the data type, followed by the name of the variable, followed by a semicolon. For example: int outcome;
Change the value of a variable	Write the name of the variable on the left, followed by the assignment operator, followed by the expression calculating the new value, followed by a semicolon. For example: outcome = 42;
Convert a string to an int	Call the System.Int32.Parse method. For example: System.Int32.Parse("42");
Override precedence	Use parentheses in the expression to force operands to bind to specific operators. For example: (3 + 4) * 5
Increment or decrement a variable	Use the ++ or <;$MI><;$MI> operator. For example: count++;

count = count + 1;