javascript for loop to add 1 but skip 10

Question

the task is to make a function that gives serial number to every new product so the new serial would concat the barcode with the serial but if the number is 10 it should shift to 11 (last digit zero not allowed) so the serial should be 1,2....9,11,12..19,21,22 but the product is 1,2,...11,11,12...21,21,22 I don't know why. sorry in advance if the reason is silly. that is the code:

barcode = '56734';
ary: string[] = [];
serial!: number;
finaly!: string;
newy(){  
   if (this.ary.length == 0){
    this.serial = 1
   }else if((this.ary.length + 1) %10 == 0){
    this.serial = this.ary.length + 2
   } else {
    this.serial = this.ary.length + 1
   }
   this.finaly = this.barcode + this.serial;
   this.ary.push(this.finaly)
   return this.ary   
}

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score 0 · Accepted Answer · answered Dec 20 '22 at 18:30

ok after hours of equations the answer is math rather than programming. that worked for me

barcode = '56734';
ary: string[] = [];
serial!: number;
finaly!: string;
newy(){    
   this.serial = this.ary.length +  1 + Math.floor(this.ary.length /9) 
   this.finaly = this.barcode + this.serial;   
   this.ary.push(this.finaly)
}

javascript for loop to add 1 but skip 10

1 Answers1