js IP效验，IP+掩码计算网络地址、广播地址、可用地址范围

1. IP效验

let iputils = {
};

iputils.checkIp = function(ip) {
	var exp = /^(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])$/;
	var reg = ip.match(exp);
	return reg != null;
};

2. 根据掩码获取掩码地址

iputils.getSubnetMask = function(mask) {
	 var result='';
	 var sum = 32;
	 var m = Number(mask);
	 sum = sum-m;
	 var str = "";
	 for(var i=0;i<m;i++) {
	      str = str+"1";
	 }
	 for(var j=0;j<sum;j++) {
	      str = str+"0";
	 }
	 var arr = ['','','',''];
	 for(var l=0;l<arr.length;l++) {
	      arr[l]=str.substring(l*8,(l+1)*8);
	      if(""==result)
	         result = result+iputils.add(arr[l]);
	      else result = result+"."+iputils.add(arr[l]);
	 }
		
	 return result;
}
iputils.add = function(s) {
	  //声明两个变量
	 var str='';
	 var count=0;
	 var temp = s.toString();
	 for (var i = 0; i < temp.length; i++) {
	   str=temp.substring(temp.length-i-1,temp.length-i);//字符截取
	   if(Number(str)==0)//转换成Internet类型
	        count+=0;
	   else if(i==0)
	   	count+=1;
	   else
	   	count+=iputils.addc(i);
	  }
	  return count;//返回结果
}
  //计算数字的次方
iputils.addc = function(i) { 
	 var v=1;
	 for (var j = 0; j < i; j++) {
	   v=v*2
	 }
	 return v;
}

3. 根据IP与掩码地址获取网络地址

iputils.getNetAddress = function(ip, subnetMask) {
       var ip_str = '';
       var ip_arr = ip.split(".");
       var mask_arr = subnetMask.split(".");

       var ip2 = Number(ip_arr[2]);
       var ip3 = Number(ip_arr[3]);
       var mask2 = Number(mask_arr[2]);
       var mask3 = Number(mask_arr[3]);
	
       ip_str=(ip2&mask2)+"."+(ip3&mask3);
       ip_str = ip_arr[0]+"."+ip_arr[1]+"."+ip_str;
       return ip_str;
}

4. 根据网络地址与主机位0的个数获取广播地址

//获取广播地址
iputils.getBroadcastAddress = function(netAddress, localNumber){
	var netArr = netAddress.split(".");
	var length = netArr.length;
	var more = localNumber%8;
	var except = parseInt(localNumber/8);
	if(more!=0)
		++except;
	except = length - except;
	for(var i=except;i<length;i++) {
		var netPart = Number(netArr[i]);
		var temp = iputils.convertBinary(netPart);
		if(""==temp) {
			temp="00000000";
		}
		if(i==except) {
			if(more==0) {
				temp="11111111";
			}else {
				temp = temp.substring(0,8-more)+iputils.getNumber(more);
			}
			var result = Number(temp);
			result = iputils.binaryToDecimal(result);
			netArr[i]=result+"";
		}else {
			netArr[i]="255";
		}
	}
	return netArr.join(".");
}

//获取主机位0的个数
iputils.getLocalNumber = function(subnetMask){
    var maskArr = subnetMask.split(".");
    var length = maskArr.length;
    for(var i=0;i<length;i++) {
        var maskPart = Number(maskArr[i]);
        var temp = iputils.convertBinary(maskPart);
        if("11111111"!=temp) {
            var index = temp.lastIndexOf("1")+1;
            var result = (8-index)+(length-i-1)*8;
	    return result;
	}
    }
    return 0;
}
//转成二进制
iputils.convertBinary = function(sum){
    var binary = "";
    while (sum != 0 && sum != 1) {
	    binary=binary.slice(0,1)+(sum % 2)+binary.slice(1)
        sum = parseInt(sum / 2);
        if (sum == 0 || sum == 1) {
        	binary=binary.slice(0,1)+(sum % 2)+binary.slice(1)
        }
    }
    return binary.toString();
}
//获取1的字符串
iputils.getNumber = function(number){
	var result = "";
	for(var i=0;i<number;i++) {
		result="1"+result;
	}
	return result;
}

//二进制转十进制
iputils.binaryToDecimal = function(binaryNumber){
    var decimal = 0;
    var p = 0;
    while(true){
      if(binaryNumber == 0){
	    break;
      }else {
	    var temp = binaryNumber%10;
	    decimal += temp*Math.pow(2, p);
	    binaryNumber = parseInt(binaryNumber/10);
	    p++;
       }
    }
    return decimal;
}

5. 根据IP与掩码地址获取网络地址

//根据IP与掩码获取IP范围
iputils.getIpRange = function(ip, mask) {
	var subnetMask = iputils.getSubnetMask(mask);
	var localNumber = iputils.getLocalNumber(subnetMask)
	var netAddress = iputils.getNetAddress(ip, subnetMask)
	var broadcastAddress = iputils.getBroadcastAddress(netAddress, localNumber)
	var result = iputils.getIpRangez(netAddress, broadcastAddress);
	console.log(subnetMask)
	console.log(netAddress)
	console.log(localNumber)
	console.log(broadcastAddress)
	console.log(iputils.getIpRangez(netAddress, broadcastAddress))
	return result;
};

//获取Ip范围
iputils.getIpRangez = function(netAddress, broadcastAddress){
	var netArr = netAddress.split(".");
	var number = Number(netArr[3])+1;
	netArr[3] = number+"";
	var broadcastArr = broadcastAddress.split(".");
	number = Number(broadcastArr[3])-1;
	broadcastArr[3] = number+"";
	return netArr.join(".")+"-"+broadcastArr.join(".");
}