Using Javascript or jQuery, how can I check if an external link is available?
An $.ajax()
call is not available as it violates SOP (same problem as her
Yes, in browsers that support flash you can use this plugin. It has the same api as native xhr. Further if there is no flash plugin in browsers you still can access the other domain. In some browsers if your target domain response has the following headers there will not be an error.
Access-Control-Allow-Methods: GET, POST, OPTIONS
Access-Control-Allow-Credentials: true
Access-Control-Allow-Origin: *
Access-Control-Allow-Headers: Content-Type, *
Replace * with appropriate domains.
All above techniques are applicable only if the second domain is under your control. If not then you have to use a proxy as Jleagle said.