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several methods

Here are the ways to access various parts of this document:

To access the link, refer to

document.links[0]

To access the image, refer to

document.images[0]

document.images[“imgHome”]

To access the form, refer to

document.forms[0]

document.forms[“frmSubscribe”]

Additionally, all the attributes of links, images, and so on all become properties of the objects. For exam-

ple,

document.images[0].src

is the code to get the

src

attribute of the first image.

Finally, several methods exist on the BOM

document

object. One of the most often used is the

write()

method or its sibling

writeln()

. Each of these methods accepts one argument, which is a string to write

to the document. The only difference is, as you might expect,

writeln()

adds a new line (

) character

at the end of the string.

Both methods insert the string content in the location where it is called. The browser then treats the doc-

ument as if the string were part of the normal HTML in the page. Consider the following short page:

<html>

<head>

<title>Document Write Example</title>

</head>

<body>

<h1><script type=”text/javascript”>document.write(“this is a

test”)</script></h1>

</body>

</html>

The page is displayed in the browser as if it were the following:

<html>

<head>

<title>Document Write Example</title>

</head>

<body>

</body>

</html>

You can use this functionality to dynamically include external JavaScript files as well. For example:

<html>

<head>

<title>Document Example</title>

document.write(“<script type=\”text/javascript\” src=\”external.js\”>”

+ “</scr” + “ipt>”);

</script>

</head>

<body>

</body>

</html>

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JavaScript in the Browser

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