Code could be reduced and flexibility increase by adding a "headers" key to the ajaxSettings defaults, which could be used to specify additional headers to send with each AJAX request.

The following documents what changes need to be made:

Add a "headers" key to the ajaxSettings defaults:

ajaxSettings: {

global: true,

type: "GET",

timeout: 0,

contentType: "application/x-www-form-urlencoded",

processData: true,

async: true,

data: null,

headers: {"X-Requested-With": "XMLHttpRequest"}

},

Remove the following lines:

Set header so the called script knows that it's an XMLHttpRequest

xml.setRequestHeader("X-Requested-With", "XMLHttpRequest");

Make sure the browser sends the right content length

if ( xml.overrideMimeType )

xml.setRequestHeader("Connection", "close");

Add the following line:

// supply any additional mapped headers

for( var k in s ) xml.setRequestHeader(k, s[k]);

That's it! This will make it easier to add headers to a request, reduces the code and removes the old "Connection: close" fix for older Gecko-based browsers (which are no longer supported by jQuery anyway.)

-Dan