asp.net - 従来のASPで.net Webサービスを呼び出す方法は?

Question

こんにちは、私は Web サービスの初心者で、Classic ASP を介してサービスを呼び出したいと考えています。

<%
   If Request.ServerVariables("REQUEST_METHOD") = "POST" Then
   Dim xmlhttp
   Dim DataToSend
   DataToSend="val1="&Request.Form("text1")&"&val2="&Request.Form("text2")
   Dim postUrl
   If Request.Form.Item("Operation")="Sum" Then
    postUrl = "//localhost/Test_ASP_Service1/Service1.asmx/Sum"
  end if    
  Set xmlhttp = server.Createobject("Msxml2.ServerXMLHTTP.4.0")
  xmlhttp.Open "POST",postUrl,true
  xmlhttp.setRequestHeader "Content-Type","application/x-www-form-urlencoded"
  xmlhttp.send DataToSend
  Response.Write DataToSend  & "<br>"
  Response.Write(xmlhttp.responseText)
Else
  Response.Write "Loading for first Time"  
  End If
 %>
<FORM method=POST name="form1" ID="Form1">
 Enter the two Values to perform Operation<BR>
  <select name="Operation">Select Operation<option value="Sum">Sum</option></select> 
  <INPUT type="text" name="text1" ID="Text1">
  <INPUT type="text" name="text2" ID="Text2">
 <INPUT type="submit" value="GO" name="submit1" ID="Submit1">
</form>