DwinsHs_GetRemoteSize function

Gets the size of the remote file or the length of the response at the given URL.

Declaration:

type
  TReadMethod = (rmGet, rmPost, rmActive, rmPassive);
#ifdef UNICODE // For UNICODE Inno Setup
function DwinsHs_GetRemoteSize(URL, Agent: AnsiString; Method: TReadMethod): Int64;
#else // For ANSI Inno Setup
function DwinsHs_GetRemoteSize(URL, Agent: AnsiString; Method: TReadMethod): LongInt;
#endif

Parameters:

• URL: AnsiString

  The full address of the file to check the size of, or the address of server script to check the length of its response. the "http", "https" and "ftp" schemes are supported. Optional username, password and port number can be included. For "http" and "https" schemes, an optional parameters string can be included too.

  Format:

  [<scheme>://][<username>[:<password>]@]<host>[:<port>] [/<path>][?<parameters>]

  For example:

  http://username:password@www.mywebsite.com:8080/images/file.jpg
  https://www.mywebsite.com/license/verify.php?license_key=xxx-xxx-xxx-xxx&license_type=2
  ftp://username:password@www.mywebsite.com:2121/images/file.jpg

• Agent: AnsiString

  Specifies an user agent string. Your server can use the string to determine whether the request is sent by your installation package, or determine which installation package sends the request, etc.

• Method: TReadMethod

  Specifies the HTTP methods for an "http" or "https" request. Or specifies the transfer mode for an "ftp" request. It can be one of the following values:

  • rmGet: Use the GET method, only for "http" or "https" request.
  • rmPost: Use the POST method, only for "http" or "https" request.
  • rmActive: Use the active FTP mode, only for "ftp" request.
  • rmPassive: Use the passive FTP mode, only for "ftp" request.

Return:

Returns the file size or the response length in bytes if successful, a negative integer otherwise, its absolute value indicates the error code:

• CONNECT_ERROR_NETWORK (1): There is no Internet connection, or if all possible Internet connections are not currently active.
• CONNECT_ERROR_OFFLINE (2): The computer is in offline mode.
• CONNECT_ERROR_INITIALIZE (3): Failed to initialize the installation package for accessing Internet.
• CONNECT_ERROR_OPENSESSION (4): Failed to open the FTP or HTTP session.
• CONNECT_ERROR_CREATEREQUEST (5): Failed to create an HTTP request handle.
• CONNECT_ERROR_SENDREQUEST (6): Failed to send request to the HTTP server.
• Greater than or equal to 400: The HTTP status code.

If the error code is between 1 and 6, you can call the DllGetLastError function to retrieve a specific error message.

Note:

If you want fetch the length of response at the given URL, the Content-Length entity-header field is required on response from your server.