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

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原文链接：http://www.cnblogs.com/kfx2007/archive/2012/08/16/2642729.html

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#javascript #ViewUI

本文介绍JavaScript客户端技术的使用，包括确认对话框、超时时间设置、DOM元素操作、用户输入获取、HTML内容设置、浏览器数据存储、HTTP请求发送及canvas元素绘图等关键功能，并提醒开发者注意避免在代码中插入多余的换行符导致语法错误。

1.2 Client-Side JavaScript:

confirm()函数：用于弹出确认对话框,setTimeout()函数用于，设置超时时间。

	<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 拼写错误将导致程序不能正常运行。

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.

转载于:https://www.cnblogs.com/kfx2007/archive/2012/08/16/2642729.html