JavaSript For Loop

Last Updated Jul 29, 2015, 07:00:14 PM

JavaSript For Loop

The for loop statement creates a loop that consists of three optional expressions, enclosed in parentheses and separated by semicolons, followed by a statement or a set of statements executed in the loop.


An expression (including assignment expressions) or variable declaration. Typically used to initialize a counter variable. This expression may optionally declare new variables with the var keyword.


An expression to be evaluated before each loop iteration. If this expression evaluates to true, the statement is executed. This conditional test is optional. If omitted, the condition always evaluates to true. If the expression evaluates to false, execution skips to the first expression following the for construct.


An expression to be evaluated at the end of each loop iteration. It occurs before the next evaluation of the condition. The final expression is used to update or increment the counter variable.


A statement that is executed as long as the condition evaluates to true. To execute multiple statements within the loop, use a block statement ({ ... }) to group those statements. To execute no statement within the loop, use an empty statement (;).


In the above example, the variable n initialized with 0, it checks if the variable n is less than 9, then it will print that variable while the value of n keeps increasing until the condition becomes false

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Other JavaScript loop statements you might want to learn

JavaScript while loop

JavaScript do while loop

JavaScript break statement

JavaScript continue statement

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Browser compatibility
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Sources and Credits

The source of the content has been referred and updated with Mozilla Developer Network and W3C Organization

Last Updated Jul 29, 2015, 07:00:14 PM