JavaScript StatementsIn HTML, JavaScript statements are "instructions" to be "executed" by the web browser. Show
This statement tells the browser to write "Hello Dolly." inside an HTML element with id="demo": Exampledocument.getElementById("demo").innerHTML = "Hello Dolly."; Try it Yourself » For a tutorial about Statements, read our JavaScript Statements Tutorial. JavaScript Statement IdentifiersJavaScript statements often 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:
Example let x, y, z; // Statement 1 Try it Yourself » JavaScript ProgramsA computer program is a list of "instructions" to be "executed" by a computer. In a programming language, these programming instructions are called statements. A JavaScript program is a list of programming statements. In HTML, JavaScript programs are executed by the web browser. JavaScript StatementsJavaScript statements are composed of: Values, Operators, Expressions, Keywords, and Comments. This statement tells the browser to write "Hello Dolly." inside an HTML element with id="demo": Exampledocument.getElementById("demo").innerHTML = "Hello Dolly."; Try it Yourself » Most JavaScript programs contain many JavaScript statements. The statements are executed, one by one, in the same order as they are written. JavaScript programs (and JavaScript statements) are often called JavaScript code. Semicolons ;Semicolons separate JavaScript statements. Add a semicolon at the end of each executable statement: Examples let a, b, c; // Declare 3 variables Try it Yourself » When separated by semicolons, multiple statements on one line are allowed: On the web, you might see examples without semicolons. JavaScript White SpaceJavaScript ignores multiple spaces. You can add white space to your script to make it more readable. The following lines are equivalent: let person = "Hege"; A good practice is to put spaces around operators ( = + - * / ): JavaScript Line Length and Line BreaksFor best readability, programmers often like to avoid code lines longer than 80 characters. If a JavaScript statement does not fit on one line, the best place to break it is after an operator: JavaScript Code BlocksJavaScript statements can be grouped together in code blocks, inside curly brackets {...}. The purpose of code blocks is to define statements to be executed together. One place you will find statements grouped together in blocks, is in JavaScript functions: Example function myFunction() { Try it Yourself » In this tutorial we use 2 spaces of indentation for code blocks. JavaScript KeywordsJavaScript statements often start with a keyword to identify the JavaScript action to be performed. Our Reserved Words Reference lists all JavaScript keywords. Here is a list of some of the keywords you will learn about in this tutorial:
JavaScript keywords are reserved words. Reserved words cannot be used as names for variables. What are the three types of statements in JavaScript?JavaScript Statements. What are different JavaScript control statements?JavaScript has two types of control statements. Conditional and Iterative (Looping) with their particular uses. We learned about conditional statements like IF, IF-ELSE, and SWITCH, along with their respective syntaxes. And for Iterative Statements, we learned about WHILE, DO-WHILE and FOR along with syntaxes.
What are different types of statements written inside above JS?JavaScript. Why do we use statements in JavaScript?Statements are used in JavaScript to control its program flow. Unlike properties, methods, and events, which are fundamentally tied to the object that owns them, statements are designed to work independently of any JavaScript object.
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