Contract Not sending ether to other account

Question

I have created a contract which store the address of the users and i want to send 1 ether all the users stored in array.

Here is my code

contract project{

    address public user;
    bytes32[10] name;
    address[10] customer;
    uint public i=0;
    function project(){
        user=msg.sender;
    }



    function add(bytes32 _name){
        name[i]=_name;
        customer[i]=msg.sender;
        i++;
    }

    function get_address() constant returns(address[10]){
        return customer;
    }

    function reward() {
        for(uint i=0;i<10;i++)
        {
            customer[i].send(1);
        }

    }

}

When i call the method reward metamask executed the transaction but ether is not transferred.

Please help me.

Answer 1

You're trying to make the contract send funds it doesn't have. It needs ether to draw from. The balance would start at 0, so you need to add a function() payable{} and send some ether to work with.

I've marked a section of the code *** unsafe *** to avoid misunderstanding. There are deeper concerns about handling money this way. A good next step is to check the success/fail of the send() operation and then respond differently. I have it emitting a failure message or a success message.

I added some event emitters so you can see what's going on.

Hope it helps.

contract project{

  address public user;
  bytes32[10] name;
  address[10] customer;
  uint public i=0;

  event LogDep (address sender,    uint amount, uint balance);
  event LogSent(address recipient, uint amount, uint balance);
  event LogErr (address recipient, uint amount, uint balance);

  function project(){
    user=msg.sender;
  }

  function depositFunds() public payable returns(bool success) {
    LogDep(msg.sender, msg.value, this.balance); 
    return true;
  }

  function add(bytes32 _name){
    name[i]=_name;
    customer[i]=msg.sender;
    i++;
  }

  function get_address() constant returns(address[10]){
    return customer;
  }

  function reward() {
    for(uint i=0;i<10;i++)
    {

        // *** unsafe pattern ***

        if(customer[i].send(1)) {
            LogSent(customer[i], 1, this.balance);
        } else {
            LogErr(customer[i], 1, this.balance);
        }
    }
  }
}

Here it is in Remix to show it working.

If you haven't seen Remix before, go here https://ethereum.github.io/browser-solidity and just paste the code into the compiler. You can interact with the contract functions.

Step 1: Create the contract

Step 2: Send the contract some funds

10 wei is just enough to send 1 to all 10 customers. If you send less, you'll start seeing failed sends in Step 3.

Step 3: send txn to reward()

Be sure to NOT send wei/eth this time, because this function isn't payable.