Data Types

Data Types

Data types define what information is stored

The most used of them are:

int	Whole number.
double	Floating point number.
string	Sequence of characters (text).
char	Represents a single symbol.
bool	Can have only 2 values - true or false.

Reading And Printing Data

• Console.ReadLine(); - reading data.
• Console.WriteLine(); - printing data.

Make sure using System; is added in order to use them.

Variables

The variables are used to store data of certain type.

Their value can be changed any time.

Example of variables definitions:

using System; namespace csharp { class Program { static void Main(string[] args) { // Declaring variable with value: int num1 = 5; // Declaring variable and setting value later: int num2; num2 = -3; // String values are set between double quotes. string name = "Alex"; // Char values are set between single quotes. char letter = 'c'; bool boolVariable1 = true; bool boolVariable2 = false; } } }

Basic program example:

Write a program that prints "Starting the program." Afterwards it must read a word and print it back.

Solution:

using System; namespace csharp { class Program { static void Main(string[] args) { Console.WriteLine("Starting the program."); // Read user's input string read = Console.ReadLine(); // Print back the user's input: Console.WriteLine(read); } } }

Input:

blue

Output:

Starting the program. blue

Explanation:

• using System; is added so Console.ReadLine() and Console.WriteLine() can be used.
• Console.WriteLine() is used to print message to the user.