JavaScript: The Definitive Guide, 6th Edition Chapter 1 Note 1

1.2 Client-Side JavaScript:

 

confirm()函數：用於彈出確認對話方塊,setTimeout()函數用於，設定逾時時間。

<script type="text/javascript">function moveon(){var answer = confirm("Ready to move On?");if(answer){  window.location = "Http://Google.com";  }};setTimeout(moveon,6000);</script>

　　confirm 拼字錯誤將導致程式不能正常運行。

2.The Example demonstartes a number of core JavaScript language features, and also demonstares important client-side JavaScript techniques:

     1.How to find elements in a document.

     2.How to get user input from form input elements

     3.How to set the HTML content of document elements.

     4.How to store data in browser.

     5.How to make scripted HTTP requests.

     6.How to draw graphics with the <canvas> element.

If a line break appears after any of these words(before any other tokens),JavaScript will always interpret 

that line break as a semicolon.For example,if you write:

Return true;

　　JavaScript assumes you meant:

return; true;

　　However,you probably meant:

return true;

　　What this means is that you must not insert a line break between retrun,break,or continue and the expression that follows the keyword.If you do insert a line break,your code is likely to failin a nonobvious way that is difficult to debug.