Question

How can I send a JavaScript array as a JSON variable in my AJAX request?

Answer 1

This requires you to serialize the javascript array into a string, something that can easily be done using the JSON object.

var myArray = [1, 2, 3];
var myJson = JSON.stringify(myArray); // "[1,2,3]"
....
xhr.send({
    data:{
        param: myJson
    }
});

As the JSON object is not present in older browsers you should include Douglas Crockfords json2 library

If you already rely on some library that includes methods for encoding/serializing then you can use this instead. E.g. ExtJs has Ext.encode