How to load account address from polkadot extension?

Question

I have following code so far.

import { useSubstrateState } from './../substrate-lib'
import { web3FromSource } from '@polkadot/extension-dapp'

const { api, currentAccount } = useSubstrateState()    
const getFromAcct = async () => {
        const {
          address,
          meta: { source, isInjected },
        } = currentAccount
    
        if (!isInjected) {
          return [currentAccount]
        }
    
      
        const injector = await web3FromSource(source)
        return [address, { signer: injector.signer }]
      }

And transaction as:

const fromAcct = await getFromAcct()
const unsub = await txExecute
              .signAndSend(...fromAcct, ({ status, events }) => {
                txResHandler(status, events)
              })
              .catch(txErrHandler)

But it doesn't call the polkadot extension.
It gives error Cannot destructure property 'address' of 'currentAccount' as it is null.

Answer 1

You issue lies here -

const {
  address,
  meta: { source, isInjected },
} = currentAccount

As the error suggests, in this case currentAccount === null, so trying to extract address from it is invalid.

Either check for the null value before attempting to deconstruct, or don't allow null returns for currentAccount from useSubstrateState()

Answer 2

You should probably try the web3Accounts method first.

According to @polkadot/extension-dapp package's document, here are the differences

• web3Accounts(): Promise<InjectedAccountWithMeta[]> - returns a list of all the injected accounts, accross all extensions (source in meta)
• web3FromSource(name: string): Promise<InjectedExtension> - Retrieves a provider identified by the name

If you choose web3FromSource, make sure you pass to it the correct extension name.

In the case of Polkadot.js extension, the name should be polkadot-js:

const injector = await web3FromSource('polkadot-js');