AJAX in Sharepoint 2010 Web Parts

Question

I want to use HighCharts in Sharepoint Web Parts. So, I put necessary JS files in 14 hive folder and everything works fine. This is my ScriptLink Tag:

<SharePoint:ScriptLink ID="ScriptLink1" Name="<% $SPUrl:~SiteCollection/STYLES/MyWebPart/Highcharts/js/highcharts.js%>" runat="server" />

But when I want to use AJAX, there is a problem:

I don't know how can I address the AJAX URL:

function requestData() {
        $.ajax({
            url: ' ?? ',
            success: function(point) {
                var series = chart.series[0],
                shift = series.data.length > 20;
                chart.series[0].addPoint(point, true, shift);
                setTimeout(requestData, 1000);    
            },
            cache: false
        });
}

I have tested this solution without a chance:

url: '< % = ResolveUrl("$SPUrl:~SiteCollection/STYLES/MyWebPart/data.json") % >'

Even if I use full URL I got Runtime Error with FireBug (Net Tab): (In this situation if I use incorrect URLs I got 404 Not Found Error)

url: 'http://sharepoint/_layouts/1033/STYLES/MyWebPart/data.json'

At last if I use HighChart URL with "crossDomain: true" nothing happens:

url: 'http://www.highcharts.com/studies/live-server-data.php'

It seems Web Parts have some problems with AJAX.

Any help would be greatly appreciated

Answer 1

Due to this line:

<add name="JSONHandlerFactory" path="*.json" verb="*" type="System.Web.Script.Services.ScriptHandlerFactory, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" resourceType="Unspecified" preCondition="integratedMode" />

in the <system.webServer><handlers> section in the standard SharePoint 2010 web.config. SharePoint (well in fact ASP.NET) assumes that any file with the extension .json should be json enabled web services.

So if your data.json is just data then you have to give it another extension.