When we use data in our programs, it’s good practice to save them in a variable. A variable is basically like a box in our computer memory where we can store values used in our code.
In C#, data types and variables are closely intertwined. Remember how C# is strongly-typed? Every time we declare a variable, we have to specify what kind of data type that variable is going to hold.
There are two ways we can assign variables. We can do it on two lines:
// Declare an integer int myAge; myAge = 32;
Or, we can be more concise and just do it on one:
// Declare a string string countryName = "Netherlands";
In each case, we first write the data type, then the variable name, then use the equals sign
= to assign the variable a value.
Once we’ve defined a variable, we can use them throughout our program. For example, here’s a short program that prints a few math equations to the console:
int evenNumber = 22; int oddNumber = 45; Console.WriteLine(evenNumber + oddNumber); // Prints 67 Console.WriteLine(oddNumber - evenNumber); // Prints 23
If we want to change the values, it’s only necessary to change it in one place instead of everywhere it is used.
To practice creating variables, we’re going to write a program that prints information about a dog to the console. We’ll be working with the types
First, create two string variables.
The first one is called
name and has the value
The second one is called
breed and has the value
Next, create a variable to hold the age. Name the variable
age and store the value
Next, create a variable to hold the weight. Name the variable
weight and store the value
Next, create a variable that can be either true or false. Name the variable
spayed and set it to
Console.WriteLine() to print each variable to the console.