Question

I have this script that calls a .net WebService

msg = $.toJSON(
        $.ajax({
            type: "POST",
            url: "http://[url]/ETS.UI/WebServices/LocationService.asmx/GetMappingLocationDetails",
            contentType: "application/json; charset=utf-8",
            data: $.toJSON({'componentId':994}),
            dataType: "json",
            async: false
        }).responseText
);

And I recieve the following value in the msg variable:

""{\"d\":\"{\\\"ComponentId\\\":994,\\\"Latitude\\\":32.219627009236405,\\\"Longitude\\\":-110.96843719482422,\\\"LocationName\\\":\\\"Tucson\\\",\\\"StreetAddress\\\":\\\"7201 E 22nd Street \\\",\\\"City\\\":\\\"Tucson\\\",\\\"State\\\":\\\"AZ\\\",\\\"PostalCode\\\":null}\"}""

I have no idea why this would format this way, seems to only do this in responseText.

Does anyone have any ideas?

Answer 1

As SLaks mentioned, synchronous AJAX is a Very Bad Idea^®. If you’re looping over items to plot on a map, you don’t want to make a server call for every item anyway – you’ll get absolutely horrid performance with more than just a couple items due to the cumulative latency of all the round-trips.

A much better method would be to submit an array of componentIds to your server. The server can then loop over the array of IDs and return an array of lat/longs and whatever else for you to plot on the map.

    $.ajax({ 
        type: "POST", 
        url: "http://[url]/ETS.UI/WebServices/LocationService.asmx/GetMappingLocationDetails", 
        contentType: "application/json; charset=utf-8", 
        data: $.toJSON([{'componentId':994},{'componentId':995}, ... ]), 
        dataType: "json", 
        async: true,
        success: callbackFunctionThatPlotsReturnedPoints
    });

You might also want to check out this plugin which makes calling ASMX services from jQuery a little easier.