Ext.NET DirectMethod calls are failing when my site runs through CloudFlare

Website, Application, Performance
1

We have a site which uses Ext.NET for its interface

Part of this interface uses Ext.NET DirectMethods to trigger c# code from a JavaScript call. For example…

c# code…

[DirectMethod]
public static void ExampleDirectMethod(string variablePassed)
{
}

js code…

var runTest = function() {
    Ext.net.DirectMethods.ExampleDirectMethod('testing', {
        success: function (result) {
            console.log((new Date()) + ' - ExampleDirectMethod - result = success');
        },
        failure: function (result) {
            console.log((new Date()) + ' - ExampleDirectMethod - result = ' + JSON.stringify(result));
        }
    });
}

This code worked fine until I set my site to run through Cloudflare

When the site is running through cloudflare, I can see the ajax calls which are triggered by my runTest() function, but instead of the result being a json string, the result is the html of the page that I am running the page from

Normal AJAX calls work fine, it’s just these Ext.net.DirectMethod ones which are failing

I can’t find any trace on the internet of anyone else having a similar problem