$(document).ready(function () {

    $('.windowClass').click(function () { // <-- bind to all window elements with that class
        $.blockUI({
            message: $('#' + this.id + '_win'),
            css: {
                top:  ($(window).height() - 40) /2 + 'px', 
                left: ($(window).width() - 200) /2 + 'px', 
                width: '200px',
                height: '40px'
            }
        });
    });

    $('[id$=_close]').click(function () { //<-- gets all elements with id's that end with close
        $.unblockUI();
        return false;
    });
});
$(window).on('resize', function () {
    $('body').children('.blockMsg').css({
        top  : ($(window).height() - 40) /2 + 'px', 
        left : ($(window).width() - 200) /2 + 'px'
    });
});​