Hacking Google Maps and Google Earth (ExtremeTech)

38 Part I — Basics

You can check the markup content for your web page by using the W3C validator at

http://validator.w3.org. Here, you can supply the URL of a web page on the Internet

or cut and paste the page content into the web form for validation. Errors and warnings will be

reported for pages that are faulty.

Figure 3-1 shows the result after running the code in Listing 3-1 through the validation service.

FIGURE3-1: Validated XHTML report.

VML (Vector Markup Language)

If you are using polylines (that is, any type of line-based markup, such as routes or bounding

boxes) on top of your Google Maps applications as an overlay, and you have clients using

Internet Explorer, you should include the Microsoft VML namespace within your XHTML

definition. Without this option, your polylines will not work.

You can ignore this requirement if you are not using polylines of any kind.

Listing 3-2 shows the suggested XHTML header to use for VML and Internet Explorer.