Strings

String is a class. It allows us to store some text. But it also gives us some useful functions to help us get part of the some text, or compare two words, or find a word.

Create a String

Here is a string variable. It is initialised with "Hello World"

String Greeting = "Hello World";

Substring - Get part of a string

String Greeting = "Hello World";

FirstWord is assigned the first five letters of Greeting. SubString() starts at the beginning includes 5 letters. FirstWord therefore contains the word "Hello"

String FirstWord = Greeting.Substring(0, 5);

SecondWord is assigned five letters from Greeting starting at array position 6. It includes the next 5 letters. SecondWord therefore contains the word "World"

String SecondWord = Greeting.Substring(6, 5);

Console.WriteLine(FirstWord);
Console.WriteLine(SecondWord);

Output:

Hello
World

If you use SubString() with one value, it will start at that value and include the rest of the text

String SecondWord = Greeting.Substring(2);

Output:

llo World

indexOf - Find the position of the first occurence of a given letter (or word) in the string.

int pos = str.indexOf("b");

pos will be 1.

Note: If the letter or word is not found, the method will return -1.

You can use a string like an array

A string is stored as an array of single letters (chars). Therefore you can refer to each letter separately as you would an item in an array:

string message = "Hello";
Console.WriteLine(message[0])

The code above would output "H" as this is the letter stored at position 0.