Get/post to RESTful web service.

Question

I need to do some GETing and POSTing to a RESTful web service from VB6. What is the best and simplest way to do that?

Answer 1

If you need to GET/POST from a REST Web service you can simply write an HTTP Request to the URL of the webservice:

http://www.webservicehost.com/webserviceop?<any parameters>

If you need to pass complex objects you will need to serialize them and then pass them as parameters

You can then get the HTTP Response in whatever format the Web service decides to return as (JSON, XML, etc)

Answer 2

You'll need to add a reference to the MSXML library:

Dim sUrl As String
Dim response As String
Dim xmlhttp

Set sUrl = "http://my.domain.com/service/operation/param"

Set xmlhttp = Server.CreateObject("MSXML2.ServerXMLHTTP")
xmlhttp.open "POST", sURL, False
xmlhttp.setRequestHeader "Content-Type", "application/x-www-form-urlencoded"
xmlhttp.send()

Dim response As String = xmlhttp.responseText

Answer 3

You can create an HttpWebRequest object:

Dim req As HttpWebRequest = HttpWebRequest.Create("http://url.to/restful/service");
req.Method = "POST" 'or "GET"

'Specify the data to send in the request
Dim text As String
text = "Data to send in request"

req.ContentType = "application/x-www-form-urlencoded" 'The type of content youre sending
req.ContentLength = CLng(text.Length) 'The length of content youre sending

'Get the request stream
Dim s As Stream
s = req.GetRequestStream()

'Write data to request stream
Dim sw As StreamWriter = New StreamWriter(s)
sw.Write(text)

'Clean up
sw.Close()
s.Close()

'Get response from request
Dim res As HttpWebResponse = req.GetResponse()

'Get output stream from response
Dim sr As StreamReader = new StreamReader(res.GetResponseStream)

'Clean up
sr.Close()
res.Close()
req = Nothing
res = Nothing