Smart Contract-Ereignis, das „Uncaught TypeError: contract_instance.NumberIsIncreased is not a function“ anzeigt

Meine Funktion ist:

function watchEvents(){
                myEvent = contract_instance.NumberIsIncreased({},{fromBlock: 'latest', toBlock: 'latest'});
                console.log(myEvent);
                myEvent.watch(function(error, result){
                    if(error){
                        console.log(error);
                    } else{
                        console.log(result);
                        document.getElementById("events").innerHTML = document.getElementById("events").innerHTML + "<br />" + JSON.stringify(result);
                    }
                });

            }

Das ist der Vertrag:

event NumberIsIncreased(address indexed whoIncreased, uint256 indexed oldNumber, uint256 indexed newNumber);


function setMyNumber(uint256 myNewNumber) public {
        NumberIsIncreased(msg.sender, myNumber, myNewNumber);
        myNumber = myNewNumber;
    }

Obwohl ich auf andere Funktionen im Smart Contract zugreifen kann, wird beim Aufrufen des Ereignisses der Fehler angezeigt Uncaught TypeError: contract_instance.NumberIsIncreased is not a function.

Ich kann Ereignisse auch im Mist-Browser verfolgen.

Ich verwende die Geth-Version: 1.7.2-stable.

Bearbeiten 1:

Ich verwende die web3.js-Version:0.14.0

Andere funktionierende Funktionen:

function getCounter(){
                contract_instance.getMyNumber(function(e,r){
                    document.getElementById("myCounter").innerText = r.toNumber();
                });
            }

function increaseCounter(){
                contract_instance.getMyNumber(function(e,r){
                    currentNumber = r;
                    currentNumber++;
                    web3.eth.getAccounts(function(e,accounts){
                        web3.personal.unlockAccount(accounts,"password", function(e,r){});
                        contract_instance.setMyNumber(currentNumber, {from:accounts[0]  , gas:200000}, function(error, result){
                            if (error){
                                console.error(error);
                            } else {
                                var txHash = result;
                                console.log(txHash);
                                callWhenMined(txHash, getCounter);
                            }
                        });
                    });
                });
            }

Meine Vertragsdatei:

pragma solidity ^0.4.0;

contract MyContract {
    address creator;
    uint256 myNumber;

    event NumberIsIncreased(address indexed whoIncreased, uint256 indexed oldNumber, uint256 indexed newNumber);

    function MyContract() public {
        creator = msg.sender;
        myNumber = 3;
    }

    function getCreator() public constant returns (address) {
        return creator;
    }

    function getMyNumber() public constant returns (uint256) {
        return myNumber;
    }

    function setMyNumber(uint256 myNewNumber) public {
        NumberIsIncreased(msg.sender, myNumber, myNewNumber);
        myNumber = myNewNumber;
    }


    function kill() public {
        if (msg.sender == creator) {
            selfdestruct(creator);
        }
    }

}