10x10 HTML5 Script Tag
0 likes520 views
The <script> tag is used to define client-side scripts like JavaScript. It contains scripting statements or links to an external script file using the src attribute. The async and defer attributes control when external scripts are executed. The type attribute is optional in HTML5, unlike HTML 4.01. The <script> tag supports external JavaScript files, inline scripts, and execution of external scripts in different ways depending on attribute values.
10x10 HTML5 Script Tag
- 1. HTML5 <script> Tag Michelle Fowler MW Art2830 Web Design
- 2. Supported by All Major Browsers
- 3. Definition of <script> Tag ● Is used to define a client-side script, such as a JavaScript ● Element either contains scripting statements or it points to an external script file through the "src" attribute
- 4. <script> Example: http://homepage.cs.uri.edu/book/javascript/javascript.htm
- 6. async Attribute Example: ● <script type="text/javascript" src="demo_async.js" async=" async"></script> ● <script async="async"> The async attribute is a boolean attribute, and can be set in the following ways: ● <script async> ● <script async="async"> ● <script async=""> Not supported by Internet Explorer
- 7. defer Attribute Example: ● <script type="text/javascript" src="demo_defer.js" defer=" defer"></script> ● <script defer="defer"> The defer attribute is a boolean attribute, and can be set in the following ways: ● <script defer> ● <script defer="defer"> ● <script defer="">
- 8. src Attribute Example: ● <script type="text/javascript" src="demo_time.js"></script> ● <script src="URL"> Possible values: ● An absolute URL - points to another web site (like src="http://www.example.com/example.js") ● A relative URL - points to a file within a web site (like src="/scripts/example.js")
- 9. Differences Between HTML 4.01 & HTML5 ● The "type" attribute is required in HTML 4, but optional in HTML5 ● The "async" attribute is new in HTML5 ● Some HTML 4.01 attributes are not supported in HTML5
- 10. Tips and Notes ● If the "src" attribute is present, the <script> element must be empty ● There are several ways an external script can be executed: ○ If async = "async": the script will be executed while the page continues the parsing ○ If async is not present and defer = "defer": the script is executed when the page has finished parsing ○ If neither async or defer is present: the script is fetched and executed immediately, before the browser continues parsing the page