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JS Tutorial

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JS Statements Reference JS Statements Reserved

JS Arrays

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JS Functions

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JS Objects

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JS Classes

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JS Sets & Maps

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JS Dates

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JS RegExpc

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JS Typed Arrays

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JS Browser BOM

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JS AJAX

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JS JSON

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JS References

JavaScript Objects HTML DOM Objects


JavaScript Statements


JavaScript Statement Identifiers

JavaScript statements start with a statement identifier to identify the JavaScript action to be performed.

Statement identifiers are reserved words and cannot be used as variable names (or any other things).

The following table lists all JavaScript statement identifiers:

Statement Description
break Exits a switch or a loop
class Declares a class
const Declares a variable with a constant value
continue Breaks one iteration (in the loop) if a specified condition occurs, and continues with the next iteration in the loop
debugger Stops the execution of JavaScript, and calls (if available) the debugging function
do ... while Executes a block of statements and repeats the block while a condition is true
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
function Declares a function
if ... else ... else if Marks a block of statements to be executed depending on a condition
let Declares a variable
return Stops the execution of a function and returns a value from that function
switch Marks a block of statements to be executed depending on different cases
throw Throws (generates) an error
try ... catch ... finally Marks the block of statements to be executed when an error occurs in a try block, and implements error handling
var Declares a variable
while Marks a block of statements to be executed while a condition is true
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