Question

As it is now I create a JavaScript object and then stringify it, put it in a hidden textbox and my code behind can read this string. I then use JSON.NET to parse the string which works fine. I now try to use ajax to post it to my web service but have some issues with how to send the string. I have tried many ways but gets the common errors like

Invalid JSON primitive: myString.

So I checked this out http://encosia.com/2010/05/31/asmx-scriptservice-mistake-invalid-json-primitive/ and it works with hard coded values but I want to use a variable.

JavaScsript to create the object:

for (var i = 0; i < results.rows.length; i++) {
        var row = results.rows.item(i);
    var customer = new Object();

        customer.id = row['id']
        customer.name = row['name']

    var customerString = JSON.stringify(customer);

    $.ajax({
        type: "POST",
        url: "synchronise.asmx/synchroniseCustomers",
        data: "synchroniseCustomers: " + customerString,
        contentType: "application/json; charset=utf-8",
        dataType: "json",
                    error: function (xhr, status) {
                alert("An error occurred: " + status);
            },
        success: function (msg) {
            alert("success");
        }
    });
}

WebMethod:

 public void synchroniseCustomers(string customerString)
        {
            JObject o = JObject.Parse(customerString);
            string id = (string)o["id"];
            string name = (string)o["name"];

If I use data: '{ FirstName: "Dave", LastName: "Ward" }'
in the example above it works but I wish to pass on a string instead.

Any suggestions?

Thanks

Answer 1

You’re pretty close, but you’d need to send that like this:

data: '{"synchroniseCustomers": ' + customerString + '}'

Also, there’s no need to accept it as a string and manually deserialize the JSON on the .NET side. .NET will handle all of that automatically if you declare the input type as a matching server-side structure.

This should help with what you’re trying to do there: http://encosia.com/2009/04/07/using-complex-types-to-make-calling-services-less-complex/