generate unique random number between a range using static class in typescript

I am creating a simple class which includes all four methods for different type of random occurrence and based on random range its generate a unique set of the random numbers between ranges.





working link=>
https://stackblitz.com/edit/typescript-qrmqc4

code=>

enum randomType

{

includeMinMax=0,

exculdeMin=1,

exculdeMax=2,

exculdeMinMax=3

}

//get random number between two range

class seedRandom

{

static maxOccur=100;

//min and max include

public static getRandomNumber(min:number,max:number)

{

return Math.round(Math.random()*(max-min)+min);

}

//if you don't wanna include max value or max exclude

public static getRandomNumberNotMax(min:number,max:number)

{

return Math.round(Math.random()*(max-(min+1))+min);

}

//if you don't wanna include min value or min exclude

public static getRandomNumberNotMin(min:number,max:number)

{

return Math.ceil(Math.random()*(max-min))+(min);

}

//if you don't wanna include min value and max value or min and max exclude

public static getRandomNumberNotMinAndMax(min:number,max:number)

{

return Math.ceil(Math.random()*((max-1)-min))+(min);

}

//get a range

public static uniqueRandomSet(min:number,max:number,total:number,
RandomType:randomType=randomType.includeMinMax):Array<number>

{

if(this.maxOccur<=total)

{

throw new Error("are you druck increase maxOccur ")

}

let rNumbers:Array<number>=[];

for(let i=0;i<this.maxOccur;i++)

{

let random;

switch(RandomType)

{

case randomType.includeMinMax:

random=this.getRandomNumber(min,max);

break;

case randomType.exculdeMin:

random=this.getRandomNumberNotMin(min,max);

break;

case randomType.exculdeMax:

random= this.getRandomNumberNotMax(min,max);

break;

case randomType.exculdeMinMax:

random=this.getRandomNumberNotMin(min,max);

break;

}

while(rNumbers.indexOf(random)===-1)

{

rNumbers.push(random);

}

if(rNumbers.length===total)

{

return rNumbers;

}

}

return rNumbers;

}

}

console.log(seedRandom.uniqueRandomSet(11,41,10,randomType.exculdeMax));