Question

I’m a JavaScript newbie, just doing a little script so that I can rotate an image + link every few days. I’m 90% sure my error is in the bottom line of code – seems to be something to do with the way quotes are used (which is confusing me a lot).

Correct code + explanation of where and why to use quotes would be much appreciated!

<SCRIPT LANGUAGE="JavaScript">

<!-- Begin
today = new Date();
date = today.getDate();
date = date - date%9;
date = date/9;
date = date%3;

arday = new Array("image 1", "image 2", "image 3");

linkday = new Array("link 1", "link 2", "link 3");

document.write("<a href= '" + linkday[date] + target="_blank" ><img src='" + arday[date] "'/> </a>");
// End -->
</SCRIPT>

Answer 1

• The language attribute is ignored by browsers, remove it. Even the type attribute can be omitted.
• If you are not parsing this page as XML, remove the <!-- -->
• Use array literals instead of new Array()
• Use var when declaring variables
• Chain variable declarations using commas. Notice one var and a series of variable declarations.
• Although single quotes are accepted, in HTML, use double quotes "" for attribute values.
• To avoid escaping double quotes, wrap strings in single quotes.
• There shall be no spaces between the opening bracket < and the tag name.
• There shall be no spaces between the attribute name, the equal sign and the opening quote.

Here’s a cleaned code:

<script>
    var today = new Date(),
        date = today.getDate(),
        arday = ["image 1", "image 2", "image 3"],
        linkday = ["link 1", "link 2", "link 3"];

    date = date - date % 9;
    date = date / 9;
    date = date % 3;

    document.write('<a href="' + linkday[date] + '" target="_blank" ><img src="' + arday[date] + '" / ></a>');​
</script>