Learn how to use the continue statement in JavaScript to skip the current iteration of a loop. Covers the syntax of the continue statement, and how to use it to improve the efficiency of your code.
The continue
statement is used to skip the current iteration of the loop and the control flow of the program goes to the next iteration.
The syntax of the continue
statement is:
continue [label];
Note: label
is optional and rarely used.
Working of JavaScript continue Statement
In a for
loop, continue
skips the current iteration and control flow jumps to the updateExpression.
// program to print the value of i
for (let i = 1; i <= 5; i++) {
// condition to continue
if (i == 3) {
continue;
}
console.log(i);
}
Output
1
2
4
5
In the above program, for
loop is used to print the value of i in each iteration.
Notice the continue
statement inside the loop.
if(i == 3) {
continue;
}
This means
continue
statement skips the third iteration.i
becomes 4 and the test condition and continue
statement is evaluated again.Note: The continue
statement is almost always used with decision making statements. To learn more, visit JavaScript if...else Statement.
To learn more about for
loop, visit JavaScript for loop.
Note: The break
statement terminates the loop entirely. However, the continue
statement only skips the current iteration.
In a while
loop, continue
skips the current iteration and control flow of the program jumps back to the while
condition.
The continue
statement works in the same way for while
and do...while
loops.
// program to calculate positive numbers only
// if the user enters a negative number, that number is skipped from calculation
// negative number -> loop terminate
// non-numeric character -> skip iteration
let sum = 0;
let number = 0;
while (number >= 0) {
// add all positive numbers
sum += number;
// take input from the user
number = parseInt(prompt('Enter a number: '));
// continue condition
if (isNaN(number)) {
console.log('You entered a string.');
number = 0; // the value of number is made 0 again
continue;
}
}
// display the sum
console.log(`The sum is ${sum}.`);
Output
Enter a number: 1
Enter a number: 2
Enter a number: hello
You entered a string.
Enter a number: 5
Enter a number: -2
The sum is 8.
In the above program, the user enters a number. The while
loop is used to print the total sum of positive numbers entered by the user.
Notice the use of the continue
statement.
if (isNaN(number)) {
continue;
}
continue
statement skips the current iteration. Then the control flow of the program goes to the condition of while
loop.In the above program, isNaN()
is used to check if the value entered by a user is a number or not.
To learn more about the while
loop, visit JavaScript while loop.
When continue
is used inside of two nested loops, continue
skips the current iteration of the inner loop. For example,
// nested for loops
// first loop
for (let i = 1; i <= 3; i++) {
// second loop
for (let j = 1; j <= 3; j++) {
if (j == 2) {
continue;
}
console.log(`i = ${i}, j = ${j}`);
}
}
Output
i = 1, j = 1
i = 1, j = 3
i = 2, j = 1
i = 2, j = 3
i = 3, j = 1
i = 3, j = 3
In the above program, when the continue
statement executes, it skips the current iteration in the inner loop and control flow of the program moves to the updateExpression of the inner loop.
Hence, the value of j = 2 is never displayed in the output.
When using nested loops, you can skip the current iteration and the control flow of the program can be passed to a label
statement's updateExpression.
But labeled continue
is rarely used in JavaScript because this makes the code harder to read and understand.
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