The code below compiles perfectly and seems to work, however when I try to call addTask like:

"item1", 1, "i1", 1

I have tried every possible variation of quotes parenthesis, brackets...

However I get the following error:

transact to taskListContract.addTask errored: Error encoding arguments: Error: invalid bytes value (arg="", type="string", value="item1")

Any help is very much appreciated.

 * @title Ownable
 * @dev The Ownable contract has an owner address, and provides basic authorization control
 * functions, this simplifies the implementation of "user permissions".
pragma solidity ^0.4.25;

contract Owned {

    address public owner;

    constructor() public {
        owner = msg.sender;

    /// @notice modifies any function it gets attached to, only allows the owner of the smart contract to execute the function
    modifier onlyOwner(){
        require(msg.sender == owner);

contract taskListContract is Owned {
    struct task {
        bytes iname;
        uint16 taskid;
        bytes icode;
        //replace for a boolean
        uint ivalue;

    uint taskCount;
    mapping(bytes => task) taskList;
    task[] taskArray;

    ///function taskListContract() public {
    ///    log0('hi');
    /// }

    function addTask(bytes name, uint16 iid, bytes code, uint val) external onlyOwner{        
        task memory tasknew = task(name, iid ,code, val);
        // log0(itemnew);
        taskList[code] = tasknew;

    function countItemList() public constant returns (uint count)  {     
        return taskCount;

    function removeTask(bytes code) external onlyOwner {
        delete taskList[code];

    function getTask(bytes code) public constant returns (bytes iname, uint val)  {   
        return (taskList[code].iname, taskList[code].ivalue);

1 Answer 1


In order to call function with bytes parameter, you need to pass parameter in hexadecimal format

enter image description here

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