This content originally appeared on DEV Community and was authored by Megha M
Today I learned about conditional statements in JavaScript. These statements are the building blocks for decision-making in any program. I understood how we can control the flow of the program based on certain conditions using if, else, else if, and even nested if blocks.
What is a Conditional Statement?
Conditional statements let the program decide what to do next based on whether a condition is true or false.
In JavaScript, we use these:
- if – checks a condition and runs the code if it’s true
- else – runs when the if condition is false
- else if – checks multiple conditions in order
- nested if – an if inside another if, used for complex logic
Flowchart: How Conditional Statements Work
[Start]
|
[Condition]
/ \
True False
/ \
[If block] [Else block]
|
[Else if block] (optional)
|
[End]
Problem I Solved: Grade Calculator
Problem Statement:
Write a program to accept a student’s mark and print the grade based on the mark.
Code:
let marks = 85;
if (marks >= 90) {
console.log("Grade A");
}
else if (marks >= 80) {
console.log("Grade B");
}
else if (marks >= 70) {
console.log("Grade C");
}
else if (marks >= 60) {
console.log("Grade D");
}
else {
console.log("Grade F");
}
- The program checks one condition at a time.
- Once a condition is true, it prints the corresponding grade and stops checking further.
- If none match, it goes to the final else block (Grade F).
Ask Yourself: What Are the Alternatives?
Can you solve the same problem using any of these?
- Ternary Operator
- switch(true) statement
- Function-based logic
- Nested if
Challenge for You:
Try rewriting this same grade logic using one of the above methods and see which is shorter or easier to understand!
What I Learned
Conditional statements help in making programs dynamic and responsive. Whether it's grading students, checking login info, or greeting users based on time — they are used everywhere. I’ll keep practicing to get more confident with different structures.
This content originally appeared on DEV Community and was authored by Megha M
Megha M | Sciencx (2025-07-10T16:09:42+00:00) If It Happens… Else Do This! Understanding Conditions in JavaScript. Retrieved from https://www.scien.cx/2025/07/10/if-it-happens-else-do-this-understanding-conditions-in-javascript/
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