| |
Basics
So how does it work? Currently, the component is really very simple as it supports only one method (server-side VBScript pseudocode given here):
Const Request_POST = 1 Const Request_GET = 2 Set xObj = Server.CreateObject("SOFTWING.AspTear") strRetVal = xObj.Retrieve(strUrl, nRequestType, strQueryString|strPostData, _ strUsername, strPassword)
The file retrieved is returned as method return value (strRetVal; errors are returned with exceptions - see the samples). If you don't need to supply Username and Password, leave them empty (""). Thus, the simplest request looks like this:
strRetVal = xObj.Retrieve("http://www.alphasierrapapa.com/iisdev/",2,"","","")
Notice that I did not supply a document - the component supports redirects! Now let's get a little bit more sophisticated: POST a form to the server with form data. How is this form data formatted? It needs to have the following form,
variable1=value1&variable2=value2...
where value1 to n need to be URL-encoded. To URL-encode a string value, use Server.URLEncode (this is also mandatory for querystrings):
strPostData = "Name=" & Server.URLEncode("Christoph Wille") & _ "&goto=" & Server.URLEncode("http://www.alphasierrapapa.com/")
The call to Retrieve now looks like this:
strRetVal = xObj.Retrieve("http://www.alphasierrapapa.com/",1,strPostData,"","")
The last thing to discuss is how to access SSL-secured items - it is as simple as replacing http:// with https:// in the strUrl parameter!
ASP Sample
In this section, there is a simple sample with two files: formpost.asp (Listing 1) which accepts a parameter and dumps it with the ALL_HTTP server variable; the second file is testretrieve.asp (see Listing 2), which uses the component to retrieve the formpost.asp file and return it to the client.
Listing 1: formpost.asp
<PRE> <% Response.Write Request.ServerVariables("ALL_HTTP") %> </PRE> <% Response.Write Request.Form("test") %> <form method=post action=""> <input type=text name="test"> <input type=submit> </form>
Listing 2: testretrieve.asp
<% Const Request_POST = 1 Const Request_GET = 2 Set xobj = CreateObject("SOFTWING.ASPtear") Response.ContentType = "text/html" On Error Resume Next ' URL, action, payload, username, password strRetval = xobj.Retrieve("http://194.8.136.102/iisdev/asptear/formpost.asp", _ Request_POST, "test=wille", "", "") If Err.Number <> 0 Then Response.Write "<b>" If Err.Number >= 400 Then Response.Write "Server returned error: " & Err.Number Else Response.Write "Component/WinInet error: " & Err.Description End If Response.Write "</b>" Response.End End If Response.Write strRetval %>
Use It Everywhere!
Due to its design, the component can be used in any Automation client as it does not rely on the ASP intrinsic objects. The following code snippet shows the Excel module sample shipping with the component (change the URLs as needed):
Const Request_POST = 1 Const Request_GET = 2 Sub DoTestComponent() On Error GoTo err_test_handler Dim xobj As Object, strRetval As String Set xobj = CreateObject("SOFTWING.ASPtear") ' URL, action, payload, username, password strRetval = xobj.Retrieve("http://194.8.136.100/formpost.asp", _ Request_POST, "test=wille", "", "") Debug.Print strRetval Exit Sub err_test_handler: If Err.Number >= 400 Then MsgBox "Server returned error: " & Err.Number Else MsgBox "Component/WinInet error: " & Err.Description End If End Sub
Installation and Download |
|
