<script type="text/javascript">
    $(function () {
        var _arr = new Array();
        _arr[0] = 1;
        _arr[0] = 2;
        _arr[0] = 3;

        $.ajax({
            url: 'webservice.aspx/function',
            data: JSON.stringify(_arr),
            type: 'POST',
            contentType: 'application/json',
            dataType: 'json',
            success: function (result) {
            }
        });
    });
</script>