Tslint: can't use Array in firebase.firestore.CollectionReference | firebase.firestore.Query why ?

[Omar-Qalei]

 const list = this.afs.collection( 'City').ref;
let queryCollection: firebase.firestore.CollectionReference | firebase.firestore.Query &  Array = list;
for (let _i = 0; _i < this.data.areaList.length; _i++) {

            if (this.data.areaList) {  queryCollection[_i] = queryCollection.where('areaList', '==', this.data.areaList[_i]);

          }
            console.log(this.data.areaList[_i]);
      }

Note: can't use let only const why and how to change bug ?
I wanna use let queryCollection .

[FiretronP75]

Array: You must specify the type of the array, like string[] for example.
Const: You will be allowed to use let instead of const, after you have a statement that assigns a new value:

let queryCollection = something;
queryCollection = somethingElse;

[Omar-Qalei]

I can't because I will get snapshot of multiple Method this is example I have more one for loop
and I need get specific data .

array = [ ];
queryCollection .get().then(snapshot => {
          snapshot.forEach(action => {
            array .push(action.data());

           console.log(array );
          }); });

Note: my website need advanced filter :)

[giladgray]

@Omar-Qalei the array is actually a const in your original code sample--you never modify the array reference itself. modifying items _in_ the array does not a new array make, so the const is correct.

(fwiw, i will rewrite code obsessively to avoid using let variables. the results are almost always worth it for legibility and maintainability.)

[Omar-Qalei]

yes please help me , I'm first time create website.
I used mat-select type multiple and text input in advanced filter.
I need advanced filter such as
https://jo.opensooq.com/en/ajloun/real-estate-for-sale/apartments-for-sale

[giladgray]

@Omar-Qalei sorry, this is not the place for advice on building web apps. the internet (especially StackOverflow) is full of useful information in this domain. best of luck!