JS exercise bank account constructor functions and prototypes solution
function Account(name, balance) {
this.name = name;
this.balance = balance;
}
Account.prototype.deposit = function(amount) {
if (this._isPositive(amount)) {
this.balance += amount;
console.info(`Deposit: ${this.name} new balance is ${this.balance}`);
return true;
}
return false;
}
Account.prototype.withdraw = function(amount) {
if (this._isAllowed(amount)) {
this.balance -= amount;
console.info(`Withdraw: ${this.name} new balance is ${this.balance}`);
return true;
}
return false;
}
Account.prototype.transfer = function(amount, account) {
if (this.withdraw(amount) && account.deposit(amount)) {
console.info(`Transfer: ${amount} has been moved from ${this.name} to ${account.name}`);
return true;
}
return false;
}
Account.prototype._isPositive = function(amount) {
const isPositive = amount > 0;
if (!isPositive) {
console.error('Amount must be positive!');
return false;
}
return true;
}
Account.prototype._isAllowed = function(amount) {
if (!this._isPositive(amount)) return false;
const isAllowed = this.balance - amount >= 0;
if (!isAllowed) {
console.error('You have insufficent funds!');
return false;
}
return true;
}
const a = new Account('a', 100);
const b = new Account('b', 0);
output.innerText += `before: a: ${a.balance}, b: ${b.balance}\n`;
a.transfer(100, b);
output.innerText += `after: a: ${a.balance}, b: ${b.balance}\n`;