sign-verify-substrate.js

import { schnorrkelVerify } from '@polkadot/util-crypto';

public signData(): void {
  this.signedData = u8aToHex(
    this.currentPair.sign(stringToU8a(this.toSign.data)));
  this.toSign.signature = this.signedData;
}
  
public verifySignature(): void {
  if (isHex(this.toVerify.signature)) {
    this.isValidSignature = schnorrkelVerify(this.toVerify.data,
      this.toVerify.signature,
      this.keyringPairPubKey);
  }
}