TypeError: Cannot read property 'push' of undefined-IONIC2

Question

I'm trying to push iterated value to array

json_resp is Json response.

my Typescript code

export class hello {

  CategoryLst:any[];

  var catIndex,BillerIndex;

  for(catIndex = 0; catIndex <= json_resp.category.length; catIndex++) {
    var Clst = json_resp.category[0].categoryName;
    this.CategoryLst.push(Clst);
  }
}

while trying to execute its throwing error as

ORIGINAL EXCEPTION: TypeError: Cannot read property 'push' of undefined

is there something am i missing ??

Answer 1

CategoryLst:any[] is just specifying the type of the array, but not assigning it, so by default the value of that array would be undefined.

In order to initialize it in the same declaration, you should do it this way:

CategoryLst:any[] = [];

Answer 2

try this

CategoryLst:any[] = [];