sqlite, localStorage save

LibStorage.ts

import LibConfig from '../lib/LibConfig';
import LibSqlite from '../lib/LibSqlite';
//
const LibStorage = {
  /**
  * save: db save
  * @param
  *
  * @return
  */
  save: async function(db : any): Promise<void>
  {
    try{
      const uint8Array = db.export();
      const base64 = this.base64encode(uint8Array);
//console.log(base64);
      const key = LibConfig.STORAGE_KEY_DB;
      localStorage.setItem(key, base64);
    } catch (e) {
      console.error(e);
      throw new Error('Error , save');
    }   
  },
  /**
  * get: get save
  * @param
  *
  * @return
  */
  get: async function(): Promise<any>
  {
    try{
      let ret = null;
      const key = LibConfig.STORAGE_KEY_DB;
  console.log("key=", key);
      const base64= localStorage.getItem(key);   
      if(base64 === null) {
        return ret;
      }   
  //console.log(base64);
      const u8 = this.base64decode(base64);
      const SQL = await LibSqlite.getSql();
      const db = new SQL.Database(u8);
      ret = db;
      return ret;
    } catch (e) {
      console.error(e);
      throw new Error('Error , get');
    }   
  }, 

  /**
  * base64encode
  * @param data:Uint8Array
  *
  * @return
  */
  base64encode: function(data:Uint8Array): any
  {
    //@ts-ignore
    return btoa([...data].map(n => String.fromCharCode(n)).join(""));
  },
  /**
  * base64encode
  * @param data:string
  *
  * @return
  */
   base64decode: function(data:string): any
   {
     //@ts-ignore
     return new Uint8Array([...atob(data)].map(s => s.charCodeAt(0)));
   },
 
}
export default LibStorage;

test.tsx

import * as React from 'react';
//import { useEffect, useState } from 'react';
import { useEffect } from 'react';
import LibSqlite from '../lib/LibSqlite';
import LibStorage from '../lib/LibStorage';

function Page() {
  useEffect(() => {
    (async() => {
//console.log(result);
    })()    
   
  }, []);
  //
  const dbSave = async function (){
    const db = await LibSqlite.getDb();
    const sql = `
    INSERT INTO Post(title, content, CategoryId, createdAt, updatedAt)
     VALUES
    (
      't1', 
      'c1',
      'ca11',
      DATETIME('now','localtime'), 
      DATETIME('now','localtime')
    );
    `;
    await db.exec(sql);    
    await LibStorage.save(db);
  }
  //
  const dbGet = async function (){
    const db = await LibStorage.get();
    if(db === null) {
      alert("Error, db is null")
      return;
    }
    await LibSqlite.setImportDb(db);
  }  
  //
  const test = async function (){
    const db = await LibSqlite.getDb();
    let res = JSON.stringify(db.exec("SELECT sqlite_version();"));
    console.log(res);
    res = JSON.stringify(db.exec(`SELECT * FROM Post;`));
    console.log(res)
  }    
  //
  return (
    <div className="container">
      <h3>Test </h3>
      <hr />
      <p>welcome, about</p>
      <hr />
      <button onClick={() => dbSave()}>save
      </button>
      <hr />
      <button onClick={() => dbGet()}>get
      </button>
      <hr />
      <button onClick={() => test()}>test
      </button>
    </div>
  );
}
export default Page;