# Programming Fundamentals/Object Examples JavaScript

## Objects

```// This class converts temperature between Celsius and Fahrenheit.
// It may be used by assigning a value to either Celsius or Fahrenheit
// and then retrieving the other value, or by calling the ToCelsius or
// ToFahrenheit methods directly.

class Temperature {
constructor() {
this._celsius = 0;
this._fahrenheit = 32;
}

get celsius() {
return this._celsius;
}

set celsius(value) {
this._celsius = value;
this._fahrenheit = this.toFahrenheit(value);
}

get fahrenheit() {
return this._fahrenheit;
}

set fahrenheit(value) {
this._fahrenheit = value;
this._celsius = this.toCelsius(value);
}

toCelsius(fahrenheit) {
return (fahrenheit - 32) * 5 / 9
}

toFahrenheit(celsius) {
return celsius * 9 / 5 + 32
}
}

// This program creates instances of the Temperature class to convert Celsius
// and Fahrenheit temperatures.
//
// References:
//     https://www.mathsisfun.com/temperature-conversion.html
//     https://en.wikibooks.org/wiki/JavaScript

main()

function main() {
var temp1 =  new Temperature();
temp1.celsius = 0
output("temp1.celsius = " + temp1.celsius);
output("temp1.fahrenheit = " + temp1.fahrenheit);
output("");

temp1.celsius = 100;
output("temp1.celsius = " + temp1.celsius);
output("temp1.fahrenheit = " + temp1.fahrenheit);
output("");

var temp2 = new Temperature();
temp2.fahrenheit = 0
output("temp2.fahrenheit = " + temp2.fahrenheit);
output("temp2.celsius = " + temp2.celsius);
output("");

temp2.fahrenheit = 100;
output("temp2.fahrenheit = " + temp2.fahrenheit);
output("temp2.celsius = " + temp2.celsius);
}

function output(text) {
if (typeof document === 'object') {
document.write(text);
}
else if (typeof console === 'object') {
console.log(text);
}
else {
print(text);
}
}
```

### Output

```temp1.celsius = 0
temp1.fahrenheit = 32

temp1.celsius = 100
temp1.fahrenheit = 212

temp2.fahrenheit = 0
temp2.celsius = -17.77777777777778

temp2.fahrenheit = 100
temp2.celsius = 37.77777777777778
```