Probably the quickest way would be to parse the HTML from the URL they provide, and then run a
string.Contains(string) against it to check for the existence of whatever you expect to see there.
eg
string link = "http://example.com/example";
string url = "http://otherperson.com/page/where/your/link/is";
string pageContents = getPageContents(url);
bool isThere = pageContents.Contains(link);
public string getPageContents(string url) {
HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(url);
using (Stream stream = request.GetResponse().GetResponseStream()) {
using (StreamReader reader = new StreamReader(stream)) {
string response = reader.ReadToEnd();
return response;
}
}
}
** This will not confirm that the link is visible or viable, as having the URL in a commented out section will still return a positive.
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