Question

I need to check if a file exists on a server using delphi..
The idea is to send a request to the server (ex : http://www.example.com/file.txt) and check the status code of the response..
how is it done in delphi?

Answer 1

You can use the TIdHTTP class (included in Delphi). Simply create an instance at run time and use its Head method to retrieve information about the server resource.

MyIdHTTP.Head(TheURL);
ResponseCode :=  MyIdHTTP.Response.ResponseCode; // 200 = OK etc
ContentLength := MyIdHTTP.Response.ContentLength;

Note that it will not download the whole resource, and the value in ContentLength is not guaranteed ok (for example for dynamically created resources)