📝 Theory (Details)

• Variables → Named storage for values. Example: int age = 25;

• Data Types:

  • int → whole numbers (e.g., 1, 42)

  • double / float → decimal numbers (e.g., 3.14)

  • string → text (e.g., "Hello")

  • bool → true/false values

  • var → lets compiler decide the type

• String Interpolation → Combine text + variables easily:

  Console.WriteLine($"Hello, {name}. You are {age} years old.");
  

💻 Practice

Step 1 – Create Variables

Edit Program.cs:

string name = "Tuong Vy";
int age = 25;
double height = 1.65;
bool isStudent = true;

Console.WriteLine($"Name: {name}");
Console.WriteLine($"Age: {age}");
Console.WriteLine($"Height: {height}m");
Console.WriteLine($"Student: {isStudent}");

Run → see output.

Step 2 – Ask User for Input

Console.Write("Enter your name: ");
string userName = Console.ReadLine();

Console.Write("Enter your age: ");
int userAge = Convert.ToInt32(Console.ReadLine());

Console.WriteLine($"Hello {userName}, you are {userAge} years old!");

Step 3 – Mini Exercise

1. Ask user for:

   • name (string)

   • favorite number (int)

   • favorite food (string)

2. Print back a sentence like:

   Hello Vy! Your favorite number is 7 and you like sushi.