javascript 判断str日期是否是今天，参数diff

function isToday(str) {    var d = new Date(str.replace(/-/g, "/"));    var todaysDate = new Date();    if (d.setHours(0, 0, 0, 0) == todaysDate.setHours(0, 0, 0, 0)) {        return true;    } else {        return false;    }}

by default7#zbphp.com

自己修改，增加diff参数。 diff为天数

function isToday(str, diff) {    var d = new Date(str.replace(/-/g, "/"));    var todaysDate = new Date();    if (!isNaN(diff)) {        d.setDate(d.getDate() + diff);    }    if (d.setHours(0, 0, 0, 0) == todaysDate.setHours(0, 0, 0, 0)) {        return true;    } else {        return false;    }}