Build Your First Blockchain App Using Ethereum Smart Contracts and Solidity
Why Ethereum Stack Exchange recommends it
Ethereum Stack Exchange users cite it as the beginner tutorial they followed when they hit Truffle, Ganache and web3 errors, so it appears mostly as the context for their debugging questions.
Recommended by 1 people across 1 different months, 2019 to 2023.
What it is
A 1.5-hour freeCodeCamp course by Dapp University that walks beginners through building a blockchain todo list app. It covers writing a Solidity smart contract, testing it, deploying with Truffle and Ganache, and building a client-side front end that lists, creates and completes tasks.
What people said
Recommends Abhiram Satputé · 2021-04 · Ethereum Stack Exchange · on “"Uncaught ReferenceError: TodoList is not defined" as I tried to call Todolist.deployed() in truffle console”
I was trying this Beginner tutorial [this video] on smart contracts and solidity. I typed truffle compile, truffle migrate and they ran without any error and I got my gas cost used up in Ganache. When I opened truffle console and typed TodoList = await TodoList.deployed() as per the tutorial, I faced this error below: Uncaught ReferenceError: TodoList is not defined at evalmachine.<anonymous>:1:7 As per the tutorial, my 2_deploy_contracts.js looks like this const TodoList = artifacts.require("TodoList.sol"); module.exports = function(deployer) { deployer.deploy(TodoList); }; Let me know what am I doing wrong, thanks in advance!
Cites EthereumFreshman · 2019-11 · Ethereum Stack Exchange · on “Error: Returned values aren't valid, did it run Out of Gas based on YT Tutorial”
I red the other Threads about this case, but couldn't fixed the problem. I got this tutorial for Scmart contracts: [this video] However the problem is that I get this error when I use "truffle migrate: Error: Returned values aren't valid, did it run Out of Gas? at ABICoder.decodeParameters (/usr/lib/node_modules/truffle/build/webpack:/~/web3-eth-abi/src/index.js:226:1) at Contract._decodeMethodReturn (/usr/lib/node_modules/truffle/build/webpack:/~/web3-eth-contract/src/index.js:465:1) at Method.outputFormatter (/usr/lib/node_modules/truffle/build/webpack:/~/web3-eth-contract/src/index.js:818:1) at Method.formatOutput (/usr/lib/node_modules/truffle/build/webpack:/~/web3-eth-contract/~/web3-core-me
Cites Andrew Biddle · 2022-02 · Ethereum Stack Exchange · on “Uncaught TypeError: Web3 is not a constructor”
I'm trying to create my first to-do app on the blockchain using solidity. I'm following this tutorial Build Your First Blockchain Todo List [this video] However, I'm getting this error when I get to this step (45:00) [LINK] I'm running truffle: Truffle v5.0.2 and have web3 installed [LINK] My metamask is also connected to my local gaunache blockchain [LINK] I would paste my code here but this error is being thrown from the truffle-contract.js (not my app.js) Let me know what other information is needed and I will happily provide it. I'm new to blockchain development but haven't found any online help regarding this specific issue.
Cites Robert Vitoriano · 2022-04 · Ethereum Stack Exchange · on “my transaction triplicates and all of them fail”
I am new to creating smart contracts, I followed this video [this video] in order to create a simple to-do list. I needed to update some code in order to make it work since the video is more than 2 years old. This is my code [LINK] , all the tests are passing, wallet connects with ganache, I did the migrations with truffle but when I try to create a new to-do from the client side I get the message:"This transaction is expected to fail. Trying to execute it is expected to be expensive but fail, and is not recommended.". I execute it anyway and it fails giving me this error [LINK] . I also noticed that the transaction triplicates [LINK] . this is my call to the createTask function on the client: cr
Cites A_bh · 2023-02 · Ethereum Stack Exchange · on “"Undefined" error when i type "todoList = await TodoList.deployed()" in truffle console”
I was trying this Beginner tutorial [this video] on smart contracts and solidity. I typed truffle compile, truffle migrate and they ran without any error . when i opened truffle console and typed TodoList = await TodoList.deployed() as per the tutorial i got error Undefined var TodoList = artifacts.require(".\TodoList.sol"); module.exports = function(deployer) { deployer.deploy(TodoList); }