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I tried to reproduce the voting tutorial from the solidity homepage [https://solidity.readthedocs.io/en/v0.5.11/solidity-by-example.html#voting]. I encountered the following problem: The code can be compiled withouth an error, but when i want to "deploy" it in the JVM i always get errors. I think the problem is connected to the constructor who expects a bytes32 array.

Here are the error messages, depending on what parameter i used with the "Deploy" button in remix.

a) "Name1", "Name2" --> creation of Ballot errored: Error encoding arguments: Error: types/values length mismatch (count={"types":1,"values":2}, value={"types":["bytes32[]"],"values":["Name1","Name2"]}, version=4.0.36)

b) ["Name1", "Name2"] --> creation of Ballot errored: Error encoding arguments: Error: invalid bytes32 value (arg="", coderType="bytes32", value="Name1", version=4.0.36)

c) "Name1" --> creation of Ballot errored: Error encoding arguments: Error: expected array value (arg="", coderType="array", value="Name1", version=4.0.36)

d) ["Name2"] --> creation of Ballot errored: Error encoding arguments: Error: invalid bytes32 value (arg="", coderType="bytes32", value="Name2", version=4.0.36)

e) Name3 --> creation of Ballot errored: Error encoding arguments: SyntaxError: Unexpected token N in JSON at position 1

f) 'Name3' --> creation of Ballot errored: Error encoding arguments: SyntaxError: Unexpected token ' in JSON at position 1

g) ['Name4'] -->creation of Ballot errored: Error encoding arguments: SyntaxError: Unexpected token ' in JSON at position 2

pragma solidity >=0.4.22 <0.7.0;

/// @title Voting with delegation.
contract Ballot {
    // This declares a new complex type which will
    // be used for variables later.
    // It will represent a single voter.
    struct Voter {
        uint weight; // weight is accumulated by delegation
        bool voted;  // if true, that person already voted
        address delegate; // person delegated to
        uint vote;   // index of the voted proposal
    }

    // This is a type for a single proposal.
    struct Proposal {
        bytes32 name;   // short name (up to 32 bytes)
        uint voteCount; // number of accumulated votes
    }

    address public chairperson;

    // This declares a state variable that
    // stores a `Voter` struct for each possible address.
    mapping(address => Voter) public voters;

    // A dynamically-sized array of `Proposal` structs.
    Proposal[] public proposals;

    /// Create a new ballot to choose one of `proposalNames`.
    constructor(bytes32[] memory proposalNames) public {
        chairperson = msg.sender;
        voters[chairperson].weight = 1;

        // For each of the provided proposal names,
        // create a new proposal object and add it
        // to the end of the array.
        for (uint i = 0; i < proposalNames.length; i++) {
            // `Proposal({...})` creates a temporary
            // Proposal object and `proposals.push(...)`
            // appends it to the end of `proposals`.
            proposals.push(Proposal({
                name: proposalNames[i],
                voteCount: 0
            }));
        }
    }

    // Give `voter` the right to vote on this ballot.
    // May only be called by `chairperson`.
    function giveRightToVote(address voter) public {
        // If the first argument of `require` evaluates
        // to `false`, execution terminates and all
        // changes to the state and to Ether balances
        // are reverted.
        // This used to consume all gas in old EVM versions, but
        // not anymore.
        // It is often a good idea to use `require` to check if
        // functions are called correctly.
        // As a second argument, you can also provide an
        // explanation about what went wrong.
        require(
            msg.sender == chairperson,
            "Only chairperson can give right to vote."
        );
        require(
            !voters[voter].voted,
            "The voter already voted."
        );
        require(voters[voter].weight == 0);
        voters[voter].weight = 1;
    }

    /// Delegate your vote to the voter `to`.
    function delegate(address to) public {
        // assigns reference
        Voter storage sender = voters[msg.sender];
        require(!sender.voted, "You already voted.");

        require(to != msg.sender, "Self-delegation is disallowed.");

        // Forward the delegation as long as
        // `to` also delegated.
        // In general, such loops are very dangerous,
        // because if they run too long, they might
        // need more gas than is available in a block.
        // In this case, the delegation will not be executed,
        // but in other situations, such loops might
        // cause a contract to get "stuck" completely.
        while (voters[to].delegate != address(0)) {
            to = voters[to].delegate;

            // We found a loop in the delegation, not allowed.
            require(to != msg.sender, "Found loop in delegation.");
        }

        // Since `sender` is a reference, this
        // modifies `voters[msg.sender].voted`
        sender.voted = true;
        sender.delegate = to;
        Voter storage delegate_ = voters[to];
        if (delegate_.voted) {
            // If the delegate already voted,
            // directly add to the number of votes
            proposals[delegate_.vote].voteCount += sender.weight;
        } else {
            // If the delegate did not vote yet,
            // add to her weight.
            delegate_.weight += sender.weight;
        }
    }

    /// Give your vote (including votes delegated to you)
    /// to proposal `proposals[proposal].name`.
    function vote(uint proposal) public {
        Voter storage sender = voters[msg.sender];
        require(sender.weight != 0, "Has no right to vote");
        require(!sender.voted, "Already voted.");
        sender.voted = true;
        sender.vote = proposal;

        // If `proposal` is out of the range of the array,
        // this will throw automatically and revert all
        // changes.
        proposals[proposal].voteCount += sender.weight;
    }

    /// @dev Computes the winning proposal taking all
    /// previous votes into account.
    function winningProposal() public view
            returns (uint winningProposal_)
    {
        uint winningVoteCount = 0;
        for (uint p = 0; p < proposals.length; p++) {
            if (proposals[p].voteCount > winningVoteCount) {
                winningVoteCount = proposals[p].voteCount;
                winningProposal_ = p;
            }
        }
    }

    // Calls winningProposal() function to get the index
    // of the winner contained in the proposals array and then
    // returns the name of the winner
    function winnerName() public view
            returns (bytes32 winnerName_)
    {
        winnerName_ = proposals[winningProposal()].name;
    }
}
Rasputin221
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    I think you want `["0x4e616d653100000000000000000000", "0x4e616d653200000000000000000000"]` (an array of two 32-byte hexadecimal values). – user94559 Sep 08 '19 at 02:05
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    Check out this link: (It worked for me) https://ethereum.stackexchange.com/questions/50310/how-to-pass-the-value-in-bytes32-array – ameesha agrawal Sep 09 '19 at 12:01
  • Thx smarx, i got the idea, although your values dont work. Thx @ameeshaagrawal, the answer in the link worked. Somehow i find the variable name a bit misleading ("proposalNames" not proposalBytes...). In addition I somehow remembered that string and bytes32 can be handled equally (whats obviosly wrong). However, thx for help. This was my first question here :) – Rasputin221 Sep 09 '19 at 19:29

2 Answers2

2

You can't use strings since the function is expecting an array composed of bytes32 values. Link posted by @Ameesha (https://ethereum.stackexchange.com/questions/50310/how-to-pass-the-value-in-bytes32-array) shows how to encode the strings to bytes32. Additionally, I learned that passing values in single quotes is wrong, and not enclosing values in square brackets is also wrong... the correct way is to use double quotes around each hex value and use square brackets to represent as a list. So, for instance, "Proposal A", "Proposal B", "Proposal C" encodes to:

["0x50726f706f73616c204100000000000000000000000000000000000000000000", 
 "0x50726f706f73616c204200000000000000000000000000000000000000000000",
 "0x50726f706f73616c204300000000000000000000000000000000000000000000"]
0

Pass the argument of []address as : [ "address","address1" ] instead of [address,address2].

sarvesh_r
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