Download as PPSX, PPTX
Uploaded byMohamed Loey
JavaScript Comprehensive Overview
The document provides an agenda for a lesson on JavaScript. It begins with an introduction on what JavaScript is, how it is used in HTML, and its capabilities. It then covers JavaScript syntax, including that it is case sensitive, how to write comments, how to define variables and use conditions, loops and arrays. It also discusses how to add JavaScript to HTML using internal and external scripts, and how to write and call functions.
More Related Content
Similar to JavaScript Comprehensive Overview
JavaScript Comprehensive Overview
- 1.
- 2. Agenda Part I: Introduction PartII: JavaScript Syntax
- 3. Agenda Part I: Introduction What is JavaScript? JavaScript In HTML JavaScript Can
- 4. What is JavaScript? •JavaScript is the first Web scripting language, developed by Netscape in 1995 • JavaScript is a scripting language. It is a lightweight, but powerful, programming language. • JavaScript similarities to Java/C++ • JavaScript is Client-side web programming • JavaScript is the most popular programming language in the world.
- 5. JavaScript In HTML •In HTML, JavaScripts must be inserted between <script> and </script> tags. • JavaScripts can be put in the <body> and in the <head> section of an HTML page. • Two Ways to Insert JavaScript: 1. Internal script 2. External script sheet
- 6. Internal script • Scriptscan be placed in the <body> or in the <head> section of HTML, and/or in both. • Example:
- 7. External script sheet •Scripts can also be placed in external files. • External scripts are practical when the same code is used in many different web pages. • JavaScript files have the file extension .js. • To use an external script, put the name of the script file in the source (src) attribute of the <script> tag
- 8. External script sheet •Example:
- 9. JavaScript Can • ChangeHTML Elements • Change HTML Attributes • Change HTML Styles (CSS) • Validate Data
- 10. Agenda Part II: JavaScriptSyntax JavaScript is Case Sensitive JavaScript Comments JavaScript Variables JavaScript Conditions JavaScript Loops JavaScript Arrays
- 11. JavaScript is CaseSensitive • In JavaScript all identifiers are case sensitive. • The variables lastName and lastname, are two different variables. • The functions myFunction and myfunction, are two different functions. • JavaScript does not interpret Var; as var.
- 12. JavaScript Comments • SingleLine Comments • Single line comments start with //. • Multi-line Comments • Multi-line comments start with /* and end with */.
- 13. JavaScript Variables • JavaScriptuses the var keyword to define variables • Example:
- 14. JavaScript Variables • JavaScriptuses the var keyword to define variables • Example:
- 15. JavaScript Conditions • InJavaScript we have the following conditional statements: 1. Use if to specify a block of code to be executed, if a specified condition is true 2. Use else to specify a block of code to be executed, if the same condition is false 3. Use else if to specify a new condition to test, if the first condition is false 4. Use switch to specify many alternative blocks of code to be executed
- 16.
- 17. JavaScript Loops • JavaScriptsupports different kinds of loops: 1. for - loops through a block of code a number of times 2. for/in - loops through the properties of an object 3. while - loops through a block of code while a specified condition is true 4. do/while - also loops through a block of code while a specified condition is true
- 18.
- 19. JavaScript Arrays • JavaScriptarrays are used to store multiple values in a single variable. • Example:
- 20. JavaScript Functions • AJavaScript function is a block of code designed to perform a particular task. • A JavaScript function is executed when "something" invokes it (calls it). • Example:
- 21.