首先先引入Base64.js文件

https://cdn.jsdelivr.net/npm/js-base64@3.7.2/base64.min.js
base64对于空格等特殊符号的加解码更加完善，不会像原生js中的加解码会在解码时出现一些小问题。

/**
 * 登录状态
 */
function loginStatus() {
    const checkbox = document.querySelector('.check input');
    const password = document.querySelector('#password');
    const phone = document.querySelector('#phone');
    phone.oninput = function() {
        localStorage.setItem('phone', JSON.stringify(phone.value));
    };
    password.oninput = function() {
        localStorage.setItem('tokens', Base64.encode(password.value.split(',').reverse().join(',')));
    };
    checkbox.onclick = function() {
        localStorage.setItem('checked', JSON.stringify(checkbox.checked));
        if (checkbox.checked == false) {
            localStorage.password = '';
            localStorage.phone = '';
        }
    };
    if (localStorage.checked) checkbox.checked = JSON.parse(localStorage.checked);
    if (checkbox.checked) {
        if (localStorage.tokens) password.value = Base64.decode(localStorage.tokens.split(',').reverse().join(','));
        if (localStorage.phone) phone.value = JSON.parse(localStorage.phone);
    }
}