jquery ajax

        $.ajax({url : 'scoreAction!exportExcel.action',type : 'POST',data : {str : str,fileName : 'score.xls'},dataType : 'json'    }).done(function(data){    if(data && data == 'success'){    window.location.href = "scoreAction!downloadFile.action?fileName=score.xls";    }else{    $.messager.show({title : '失败',msg : '导出失败！'});    }    }).fail(function(){    $.messager.show({title : '失败',msg : '导出失败！'});    });