C# 0 The Complete Reference

foreach

 loop is an excellent choice in this application because searching an array involves 

examining each element. Other types of 

foreach

 applications include such things as computing 

an average, finding the minimum or maximum of a set, looking for duplicates, and so on. 

As you will see later in this book, 

foreach

 is especially useful when operating on other types 

of collections.

Strings

From a day-to-day programming standpoint, one of the most important of C#’s data types is 

string

.

string

 defines and supports character strings. In many other programming languages, 

a string is an array of characters. This is not the case with C#. In C#, strings are objects. Thus, 

string

 is a reference type. Although 

string

 is a built-in data type in C#, a discussion of 

string

needed to wait until classes and objects had been introduced.

Actually, you have been using the 

string

 class since Chapter 2, but you did not know it. 

When you create a string literal, you are actually creating a 

string

 object. For example, in the 

statement

Console.WriteLine("In C#, strings are objects.");

the string “In C#, strings are objects.” is automatically made into a 

string

 object by C#. Thus, 

the use of the 

string

 class has been “below the surface” in the preceding programs. In this 

section, you will learn to handle them explicitly.

Constructing Strings

The easiest way to construct a 

string

 is to use a string literal. For example, here 

str

 is a 

string

 reference variable that is assigned a reference to a string literal:

string str = "C# strings are powerful.";

In this case, 

str

 is initialized to the character sequence “C# strings are powerful.”

You can also create a 

string

 from a 

char

 array. For example:

char[] charray = {'t', 'e', 's', 't'};

string str = new string(charray);

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