Most of the ERC20 examples on the internet have this function:
// ------------------------------------------------------------------------
// Don't accept ETH
// ------------------------------------------------------------------------
function () public payable {
revert();
}
However, I would like to deploy an ERC20 token on Ropsten where a user can send ETH and receive my token in return So what I have tried is deleting this function and replacing it with:
uint public sellPrice =0.5;
function setPrices(uint newSellPrice) public onlyOwner {
sellPrice = newSellPrice;
}
function buy(uint256 payload) public payable {
uint amount = safeDiv(msg.value, sellPrice);
//balances[msg.sender] += amount; //I commented this out cuz im not sure if I need it
transferFrom(owner, msg.sender, amount);
}
Sadly this doesn't work .. im getting this error : Warning! Error encountered during contract execution [Reverted]
Note: im using metamask to send the Ropsten Ether .. Im not putting any Hex Data (cuz I thought since this is the only paypal function maybe I don't need it? ) plus, I don't know the hex data for this function.. so maybe another question, how to get a hex data for unnamed function?
UPDATE
I have tried the suggest solutions below, and here is the updated contract
epragma solidity ^0.4.20;
contract SafeMath {
function safeAdd(uint a, uint b) public pure returns (uint c) {
c = a + b;
require(c >= a);
}
function safeSub(uint a, uint b) public pure returns (uint c) {
require(b <= a);
c = a - b;
}
function safeMul(uint a, uint b) public pure returns (uint c) {
c = a * b;
require(a == 0 || c / a == b);
}
function safeDiv(uint a, uint b) public pure returns (uint c) {
require(b > 0);
c = a / b;
}
}
contract ERC20Interface {
function totalSupply() public view returns (uint);
function balanceOf(address tokenOwner) public view returns (uint balance);
function allowance(address tokenOwner, address spender) public view returns (uint remaining);
function transfer(address to, uint tokens) public returns (bool success);
function approve(address spender, uint tokens) public returns (bool success);
function transferFrom(address from, address to, uint tokens) public returns (bool success);
event Transfer(address indexed from, address indexed to, uint tokens);
event Approval(address indexed tokenOwner, address indexed spender, uint tokens);
}
contract ApproveAndCallFallBack {
function receiveApproval(address from, uint256 tokens, address token, bytes data) public;
}
contract Owned {
address public owner;
address public newOwner;
event OwnershipTransferred(address indexed _from, address indexed _to);
function Owned() public {
owner = msg.sender;
}
modifier onlyOwner {
require(msg.sender == owner);
_;
}
function transferOwnership(address _newOwner) public onlyOwner {
newOwner = _newOwner;
}
function acceptOwnership() public {
require(msg.sender == newOwner);
OwnershipTransferred(owner, newOwner);
owner = newOwner;
newOwner = address(0);
}
}
contract FToken is ERC20Interface, Owned, SafeMath {
string public symbol;
string public name;
uint8 public decimals;
uint public _totalSupply;
mapping(address => uint) balances;
mapping(address => mapping(address => uint)) allowed;
function FToken() public {
symbol = "fff";
name = "FAdi Token";
decimals = 18;
_totalSupply = 1000000000;
balances[owner] = _totalSupply;
Transfer(address(0), owner, _totalSupply);
}
function totalSupply() public view returns (uint) {
return _totalSupply - balances[address(0)];
}
function balanceOf(address tokenOwner) public view returns (uint balance) {
return balances[tokenOwner];
}
function transfer(address to, uint tokens) public returns (bool success) {
balances[msg.sender] = safeSub(balances[msg.sender], tokens);
balances[to] = safeAdd(balances[to], tokens);
Transfer(msg.sender, to, tokens);
return true;
}
function approve(address spender, uint tokens) public returns (bool success) {
allowed[msg.sender][spender] = tokens;
Approval(msg.sender, spender, tokens);
return true;
}
function transferFrom(address from, address to, uint tokens) public returns (bool success) {
balances[from] = safeSub(balances[from], tokens);
allowed[from][msg.sender] = safeSub(allowed[from][msg.sender], tokens);
balances[to] = safeAdd(balances[to], tokens);
Transfer(from, to, tokens);
return true;
}
function allowance(address tokenOwner, address spender) public constant returns (uint remaining) {
return allowed[tokenOwner][spender];
}
function approveAndCall(address spender, uint tokens, bytes data) public returns (bool success) {
allowed[msg.sender][spender] = tokens;
Approval(msg.sender, spender, tokens);
ApproveAndCallFallBack(spender).receiveApproval(msg.sender, tokens, this, data);
return true;
}
uint public sellPrice =5;
function setPrices(uint newSellPrice) public onlyOwner {
sellPrice = newSellPrice;
}
function buy() public payable returns (bool success) {
uint amount = safeMul(msg.value, sellPrice); // calculates the amount
//balances[msg.sender] += amount;
if (approve(owner, amount))
transferFrom( owner,msg.sender, amount);
}
function transferAnyERC20Token(address tokenAddress, uint tokens) public onlyOwner returns (bool success) {
return ERC20Interface(tokenAddress).transfer(owner, tokens);
}
}
Sadly it didn't work .. Same error (Error encountered during contract execution [Reverted])