[Solved] How to download images from a website that are running in a loop?

Question

I assume you mean that you get a URL of the form:

"http://www.niederschlagsradar.de/images.aspx?
    jaar=-6&type=europa.precip&datum=201309171500&cultuur=en-GB&continent=europa"

And you want to extract that date and time bit so you can compare it against a list of images that you already have. So in the above, you want to get the 201309171500.

You can do that with a regular expression:

string theUrl = @"http://www.niederschlahttp://www.niederschlagsradar.de/images.aspx?
    jaar=-6&type=europa.precip&datum=201309171500&cultuur=en-GB&continent=europa";

Match m = Regex.Match(theUrl, @"&datum=(\d{12})&");
if (m.Success)
{
    string theDate = m.Groups[1].Value;
    Console.WriteLine(theDate);
}

Additional info

If you look at the HTML from the original URL, http://www.sat24.com/foreloop.aspx?type=1&continent=europa#, you’ll see some Javascript that looks like this:

var images = new Array(
    "http://www.niederschlagsradar.de/images.aspx?jaar=-6&type=europa.precip&datum=201309150000&cultuur=en-GB&continent=europa",
    "http://www.niederschlagsradar.de/images.aspx?
    // many more image URLs here
);

You need to download the HTML page, find that array in the HTML, and parse out the URLs for the individual images. Then you can download each image in turn.

Accepted Answer