JavaScript KB: Beginners Corner Topic

JavaScript uses = for it's assignment operator.

Commenting Code
JavaScript uses "//" for a single line comment and /* */ for a multiple line comment.

Common comparison operators:

Languages Focus: Development Tools

Primary development tool(s) used to develop and debug code.

In JavaScript, using a semicolon at the end of statements is optional. You might think a semicolon then is just another comment specifier but it is not. The semicolon is an optional end of statement specifier. To put two statements on a single code line, you must use a semicolon. However, the semicolon is optional, but probably confusing, when you break a single statement into multiple code lines.

Same as C/C++ but, as usual, the semicolons are optional.

Literals use either an apostrophe (also known as a single quote) as in 'Prestwood' or quoted as in "Prestwood". If you need to embed an apostrophe in an apostrophe-literal or a quote in a quoted-literal, preced it with a slash as in \' and \".

JavaScript logical operators:

Language Overview: Class-like language with limited but usable class-like and object-like functionality but no formal inheritance nor visibility control, etc.

Target Platforms: JavaScript is most commonly used to extend HTML by executing code on the browser side when visiting a website. It does have other uses including server side scripting and AJAX.

No built-in report writer but because JavaScript most frequently targets website development (a document interfaced GUI), a common solution is to simply output an HTML formatted page with black text and a white background (not much control but it does work for some situations).

To concatenate two strings, a string to an integer, or a string to a floating point number, use the + operator. JavaScript performs implicit casting when concatenating a string and a number. For example, to convert a floating point number to a string just concatenate an empty string to the number as in "" + 3.2.

An operation with only one operand (a single input). JavaScript unary operators include ++ and --. They can be used either before or after a variable as in: a++, b--, and ++a, and --b.

JavaScript is a loosely typed language. Each variable is cast in usage as string, number, boolean, function, or object.

Variable names are case sensitive.

Alternatively, you can specify the value when you declare a variable: