Writing JSON in Classic ASP page, and general (mis)understanding of Http Response

问题

I had a classic ASP page (VBscript) that generates an XML on server-side, and then Response.Writes it. The page had no client side at all.

However I needed to convert it to JSON. Since I could not find an ASP server-side way that worked (whole different subject) I did it on client-side with a Javascript code I found, finally document.writing it to the page.

THE PROBLEM is that the result is not the same: If before the http RESPONSE was only an XML, the response now is the javascript code, which writes to the browser the JSON , but not to the response. Am I understanding this right?

In other words, if before I had an xml as the response, now the response is this:

    <script type="text/javascript">     
        var xmlObj = parseXml('<%=resultXml%>');    
        var json = xml2json(xmlObj);    
        document.write(json);
    </script>

This whole block is called by the ASP inside a method like this:

sub writeJsonResult(resultXml) 
% > 

        the above javascript is here

< %     end sub
% >

So again, visibly the browser shows the JSON, but the service that uses it doesn't get the RESPONSE it needs. Is there a way to write the JSON as response? I feel I am missing something and not quite understanding this.

回答1:

AS @Quentin has pointed out;

The service is expecting to get JSON.

This means trying to get around that by processing the JSON client-side isn't going to work as that would mean you have sent back a text/html HTTP response instead of a application/json one. There is no getting around it you have to process the XML to build a JSON structure server-side then return it using

Response.ContentType = "application/json"

There are lots of JSON libraries out there for Classic ASP, some good, some great and some just plain awful. You just need to have a look through and see which one suits you, if you are looking for a recommendation ASPJSON.com is probably the most widely used library (but weirdly the site appears to be down at the moment).

If possible where the XML is generated replace this with a JSON using a library like described above, most of them support building JSON structures directly from the database, saving you on parsing and building the JSON from the XML yourself.