handsontable pro 授权码 key 生成器（JS函

function genKey(pKey,days){
 
        //生成指定长度的随机16进制码
        var g = function(len,s){
            s = s || "";
            var rev = [];
            for(var i=s.length;i<len;i++){
                rev.push(Math.floor(Math.random()*16).toString(16))
            }
            return s+rev.join("");
        }
 
        //校验Key中指定区间字符串，并生成校验码替换
        var e = function(str,s,len,vlen){
            var j = "00";
            var j2 = parseInt(j,16).toString();
            var j3 = parseInt(str.substr(s,len), 16) + j2.padStart(2, '0');
            var j4 = parseInt(j3,10);
            var key = (97 - (j4 % 97) + 1).toString(16).padStart(2, '0');
            var rev = str.substr(0,len+s) + key + str.substr(s+len+vlen);
            return rev;
        }
 
        //注册天数
        days = days || 10;
        pKey = pKey&&pKey.replace(/-/g,'');
        if(!pKey||pKey.length!==25){
            pKey=g(25);
        }
        
        //生成days天有效期
        var p = parseInt(pKey.substr(1,1),16);//时间变量（随机）
        var dayKey = ((p||9)*(days+Math.floor(Date.now()/8.64e7)))
        .toString(16)
        .padStart(5,0);//days*p 得出key
        var pKey = pKey.substr(0,18) + dayKey + pKey.substr(23);//替换Key
 
        //'\x42\x3C\x48\x34\x50\x2B';//"B<H4P+"; [1,-5,7,-13,15,-22]
        var i = [1,-5,7,-13,15,-22];
 
        pKey = e(pKey,0,6,2);//生成0-5位的校验码，并替换6-7位
        pKey = e(pKey,6,8,2);//生成6-14位的校验码，并替换14-15位
        pKey = e(pKey,14,9,2);//生成14-23位校验码，并替换23-24位
 
        return [
            pKey.substr(0,5),
            pKey.substr(5,5),
            pKey.substr(10,5),
            pKey.substr(15,5),
            pKey.substr(20,5)
        ].join("-");
    }