I am getting an error when passing (javascript array of objects) from web3js, To solidity function that takes (array of structs) as a parameter.

could you help me?

below is the code and the error

// web3js code

let slctedItems = [{name:'item1', qty:2},{name:'item2', qty:3}];

contract.methods.calcItems(slctedItems).call((err, total) => {

      // code


//solidity code

 struct Item{

        string name;
        uint qty;


function calcItems(Item[] memory _items) public view returns(uint){

       // return uint

// the error i got
Uncaught TypeError: Cannot read property 'forEach' of undefined
    at r (web3.min.js:1)
    at web3.min.js:1
    at Array.map (<anonymous>)
    at i.encodeParameters (web3.min.js:1)
    at web3.min.js:1
    at Array.map (<anonymous>)
    at Object.o._encodeMethodABI (web3.min.js:1)
    at Object.o._processExecuteArguments (web3.min.js:1)
    at Object.o._executeMethod (web3.min.js:1)
    at calc_loads (main.js:97)

online example of the issue and the code I wrote. in the link below:

I've found an issue on web3js github. see the link below:


The problem is fixed in the new release 1.2.9

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.