The syntax is very similar to an if statement, as seen below. Syntax: while (condition) { // Statements } Example: This example illustrates the use of while loop. Content is available under these licenses. In this article, we are going to see 6 different approaches to how you can iterate through in Javascript. So we are going to create a page that will make use of JavaScript and do some action with “While Loop”. The following flowchart illustrates the “while” loop statement: Here we can see that the statements will execute until the condition is true. The while statement creates a loop that executes a specified statement are deprecated, SyntaxError: Using //@ to indicate sourceURL pragmas is deprecated. The JavaScript while statement creates a loop that executes a block of code as long as the test condition evaluates to true. Indefinite loops don't have a fixed number of iterations. This is the basic difference between do while loop and while loop. While Loops. If the condition evaluates to true, the code inside the while loop is executed. JavaScript includes while loop to execute code repeatedly till it satisfies a specified condition. The while loop and the do/while are explained in the next chapters. In such situations, you would need to write loop statements to reduce the number of lines. The working of the “While Loop” is easy to understand using an example program. Then, it will check the condition, and continue to loop again if it is actually true. 13.6k 7 7 gold badges 30 30 silver badges 61 61 bronze badges. Follow edited Aug 25 '19 at 0:58. The following while loop iterates as long as n is less than In this while loop, the code executes until the condition x 5 is no longer true. Browse other questions tagged javascript while-loop or ask your own question. Statements and declarations. 2. Try the following example to implement while loop. operator, SyntaxError: missing ) after argument list, RangeError: repeat count must be non-negative, TypeError: can't delete non-configurable array element, RangeError: argument is not a valid code point, Error: Permission denied to access property "x", SyntaxError: redeclaration of formal parameter "x", TypeError: Reduce of empty array with no initial value, SyntaxError: "x" is a reserved identifier, RangeError: repeat count must be less than infinity, Warning: unreachable code after return statement, SyntaxError: "use strict" not allowed in function with non-simple parameters, ReferenceError: assignment to undeclared variable "x", ReferenceError: reference to undefined property "x", SyntaxError: function statement requires a name, TypeError: variable "x" redeclares argument, Enumerability and ownership of properties. The while loop can be thought of as a repeating if statement. The syntax of the while loop is: while (condition) { // body of loop } Here, A while loop evaluates the condition inside the parenthesis (). JavaScript supports different kinds of loops: for - loops through a block of code a number of times; for/in - loops through the properties of an object; for/of - loops through the values of an iterable object; while - loops through a block of code while a specified condition is true The JavaScript code that we are going to use is as follows. While Loop: A while loop is a control flow statement that allows code to be executed repeatedly based on the given Boolean condition. If you have read the previous chapter, about the for loop, you will discover that a while loop is much the same as a for loop, with statement 1 and statement 3 omitted. In JavaScript, the break statement is used to stop/ terminates the loop … The most basic types of loops used in JavaScript are the while and do...while statements, which you can review in “How To Construct While and Do…While Loops in JavaScript.” Because while and do...while statements are conditionally based, they execute when a given statement returns as evaluating to true. Improve this question. Test it Now. So even if the expression is FALSE then also once the statements inside the loop will be executed. The loop in this example uses a for loop … statement An optional statement that is executed as long as the condition evaluates to true. so the loop terminates. To execute multiple statements within the loop… Use //# instead, Warning: String.x is deprecated; use String.prototype.x instead, Warning: Date.prototype.toLocaleFormat is deprecated. While writing a program, you may encounter a situation where you need to perform an action over and over again. 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