Adding objects to a list in angular 2 typescript

Question

I am facing a problem to push data in a list here is my code.

labelListSelected: Label[];

onChange(object,flag){
   if(flag==false){      
           this.labelListSelected.push(object);
   }
   console.log(this.labelListSelected);
     //   console.log(object.Id+" : "+flag);
}

Answer 1

i guess its null pointer, change to:

labelListSelected: Label[] = [];