JS隐藏号码中间4位

function resetPhone(phone) {
    var str = String(phone)
    var len = str.length;
    var prev,next;
    if (len >= 7) {
        prev = str.slice(-len,-7)
        next = str.slice(-3)
        str = prev+"****"+next
    } else if (len < 7 && len >= 6) {
        prev = str.slice(-len,-4)
        next = str.slice(-2)
        str = prev + "**" + next
    }
    console.log(str)
    return str
}

function resetPhone(phone) {
    var str = String(phone)
    var len = str.length;
    if (len >= 7) {
        var reg = str.slice(-7, -3)
        return str.replace(reg, "****")
    } else if (len < 7 && len >= 6) {
        //1234567
        var reg = str.slice(-4, -2)
        return str.replace(reg, "**")
    }
}