Figuring Out How Many Items an Array Contains
In all modern JavaScript-enabled browsers, an array's length property contains the number of elements in an array. For example, the script in Figure 8-4 figures out how many images a web page holds.
Figure 8-4. How many images a web page contains
Drop this JavaScript into the bottom of a web page with images, and you'll see how it works. The critical line is ❶, which tells JavaScript to create a variable called num_images and set it to the number of images in the built-in images array. If the page has 10 images, num_images will equal 10.
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