tailieunhanh - Lecture Introduction to web engineering - Lec 20: Introduction to Java script

After studying this chapter you will be able to understand: What is JavaScript? embedding javascript with HTML, javascript conventions, variables in javascript, javascript operators, input output in javascript, javascript functions, conditional statements, looping statements. | Basharat Mahmood, Department of Computer Science, CIIT, Islamabad, Pakistan. 1 What is JavaScript? Embedding JavaScript with HTML JavaScript conventions Variables in JavaScript JavaScript operators Input output in JavaScript JavaScript functions Conditional Statements Looping Statements Basharat Mahmood, Department of Computer Science, CIIT, Islamabad, Pakistan. 2 JavaScript is a client-side scripting language JavaScript was designed to add interactivity to HTML pages JavaScript is used in millions of Web pages to improve the design, validate forms, detect browsers, create cookies, and much more Basharat Mahmood, Department of Computer Science, CIIT, Islamabad, Pakistan. 3 JavaScript is an interpreted language (means that scripts execute without preliminary compilation) JavaScript is usually embedded directly into HTML pages Everyone can use JavaScript without purchasing a license Basharat Mahmood, Department of Computer Science, CIIT, Islamabad, Pakistan. 4 JavaScript is the most . | Basharat Mahmood, Department of Computer Science, CIIT, Islamabad, Pakistan. 1 What is JavaScript? Embedding JavaScript with HTML JavaScript conventions Variables in JavaScript JavaScript operators Input output in JavaScript JavaScript functions Conditional Statements Looping Statements Basharat Mahmood, Department of Computer Science, CIIT, Islamabad, Pakistan. 2 JavaScript is a client-side scripting language JavaScript was designed to add interactivity to HTML pages JavaScript is used in millions of Web pages to improve the design, validate forms, detect browsers, create cookies, and much more Basharat Mahmood, Department of Computer Science, CIIT, Islamabad, Pakistan. 3 JavaScript is an interpreted language (means that scripts execute without preliminary compilation) JavaScript is usually embedded directly into HTML pages Everyone can use JavaScript without purchasing a license Basharat Mahmood, Department of Computer Science, CIIT, Islamabad, Pakistan. 4 JavaScript is the most popular scripting language on the internet, and works in all major browsers, such as Internet Explorer, Mozilla, Firefox, Netscape, Opera Basharat Mahmood, Department of Computer Science, CIIT, Islamabad, Pakistan. 5 JavaScript gives HTML designers a programming tool JavaScript can react to events JavaScript can read and write HTML elements JavaScript can be used to validate data JavaScript can be used to detect the visitors browser JavaScript can be used to create cookies Basharat Mahmood, Department of Computer Science, CIIT, Islamabad, Pakistan. 6 There are two methods to embed JavaScript in to HTML code Internal Script: directly written in HTML code External Script: written in separate file tag is used to tell the browser that a script follows Basharat Mahmood, Department of Computer Science, CIIT, Islamabad, Pakistan. 7 The tag is used to embed JavaScript code in HTML documents [JavaScript Statements.] JavaScript can be .