Using the Switch Statement to Determine the Day of the Week
In this article, we will explore how to use a switch statement in JavaScript to determine the day of the week based on a number input. This is a great example to demonstrate how switch statements can simplify decision-making when dealing with fixed values.
Problem Statement
Write a program using a switch statement to print the name of the day corresponding to a number between 1
and 7
. The mapping is as follows:
1 → Monday
2 → Tuesday
3 → Wednesday
4 → Thursday
5 → Friday
6 → Saturday
7 → Sunday
If the input is not within this range, display an appropriate error message.
The Code Implementation
Here’s how the switch statement can be used to achieve the desired functionality:
let day = "6";
switch(day) {
case "1":
console.log("Monday");
break;
case "2":
console.log("Tuesday");
break;
case "3":
console.log("Wednesday");
break;
case "4":
console.log("Thursday");
break;
case "5":
console.log("Friday");
break;
case "6":
console.log("Saturday");
break;
case "7":
console.log("Sunday");
break;
default:
console.log("Invalid day");
}
Understanding the Code
Variable Declaration:
A variableday
is declared and assigned a value (in this case,"6"
).Switch Statement:
The switch statement evaluates the value of
day
.Each
case
represents a possible value ofday
(e.g.,"1"
for Monday).If a match is found, the corresponding block of code executes, printing the day name.
Break Statement:
- The
break
statement prevents the execution from "falling through" to the next case.
- The
Default Case:
- The
default
block handles any input that does not match the predefined cases, ensuring the program is robust against invalid inputs.
- The
Output
For the provided example, where day = "6"
, the output is:
Saturday
Enhancements and Additional Information
Handling Numbers Directly
In the current implementation, theday
variable is a string. If you want to handle numeric input directly, you can modify the code to:let day = 6; // Now a number switch(day) { case 1: console.log("Monday"); break; case 2: console.log("Tuesday"); break; case 3: console.log("Wednesday"); break; case 4: console.log("Thursday"); break; case 5: console.log("Friday"); break; case 6: console.log("Saturday"); break; case 7: console.log("Sunday"); break; default: console.log("Invalid day"); }
OUTPUT
Saturday
Improved Error Handling
Add checks to ensure the input is within the expected range:javascriptCopyEditlet day = 8; if (day < 1 || day > 7) { console.log("Error: Please enter a number between 1 and 7."); } else { switch(day) { case 1: console.log("Monday"); break; case 2: console.log("Tuesday"); break; case 3: console.log("Wednesday"); break; case 4: console.log("Thursday"); break; case 5: console.log("Friday"); break; case 6: console.log("Saturday"); break; case 7: console.log("Sunday"); break; } }
Real-World Application
This approach can be adapted for calendar or scheduling applications.
It can also serve as a learning tool for understanding days of the week in different languages.