Typescript: error when checking if Map contains value

Question

I'm trying to check if a Map contains a value. I tested this code in typescript playground.

let userMap = new Map();

userMap.set("user1", 'displayName');
userMap.set("user2", 'displayName2');

        console.log(friendsMapNew.has("user2")); //true

But when I use this code in a google cloud function I get this error:

error TypeError: userMap.has is not a function

This is the code I use in the cloud function.

let userMap = new Map();
userMap = getUserDocument.data()['userMap']; //if i console.log this, it shows a map like this:
{ K79DFS: 'Bob' }
if (userMap.has("Bob") === true) {console.log("user exists")}

What am I doing wrong?

Thanks!

kooskoos · Accepted Answer · 2019-12-23 10:04:24Z

3

getUserDocument.data()['userMap'];

This statement returns an object and not a map.

And object doesn't have .has() function. Hence the error.

You should use this instead if "Bob is a value" in your object

Object.values(userMap).includes("Bob") === true

To check for the property name you can use:

Object.keys(userMap).includes("K79DFS") === true

edited Dec 23, 2019 at 10:04

answered Dec 23, 2019 at 9:56

kooskoos

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1 Comment

Karel Debedts Over a year ago

Thanks! Is there also a possibility to 'query' for the other value: here: K79DFS?

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