I am new at ethereum development and I am working on a simple script to execute swaps using Pancakeswap. Everything seems to be working well up to the point where I am building my transaction and calculate the tx-cost. I am using the UniswapRouterV02 abi create my Pancakeswap contract. The code: The price calculation for the swap returns correct prices.
Tag: ethereum
Importing ethers via Hardhat fails despite official testing documentation
According to the official testing documentation for Hardhat, ethers should be available implicitly within the global scope; however, it can optionally be required explicitly, like so: This fails for my local project. My package manifest seems to include the correct dependencies: My unit tests file seems to match the worked example in the Hardhat documentation also: Despite this, running the
MetaMask does not inject window.ethereum: Uncaught (in promise) TypeError: Cannot read property ‘request’ of undefined
To start, let me mention this is an in-browser project, so i can only use So a few months back I made a dapp, which worked fine even tho I never set a provider, so I guessed it used the ones given by MetaMask. However, i am using the guide here the only issue is the following code, This code
How to get a value in async function as soon as possible?
I’m working with Ethereum blockchain, but my problem my is JavaScript (async, await function). Here my code simplified: In my html In my App.js file Any help with any code of example? Thanks a lot in advance. Answer Welcome to the fantastic world of asynchronism… One way to do this would be : and in your App class :
Variable declared in data() is Undefined in Listener
I am declaring a “userid” variable in the data() section of my component. Within a mounted() method, I am initiating a listener for MetaMask. Upon changing account in MetaMask this listener is triggered. However, the “userid” (declared in data()) within the listener is undefined. How can I solve this problem? Answer Vue runs in strict mode. That means that this
Square Brackets for String in Javascript [closed]
Closed. This question needs details or clarity. It is not currently accepting answers. Want to improve this question? Add details and clarify the problem by editing this post. Closed 2 years ago. Improve this question I do not understand why I need to add square brackets around the “account” variable below, for the “accounts” variable constitutes a string. Answer From
web3 gives ” Error: Returned error: invalid sender” when broadcasting transaction
I am new to web3 and ethereum blockchain. I tried broadcasting a transaction using the following code but it always gives me an invalid sender error.The sample code is shown below. The error occurs at the below line Please help me know how to fix this problem. Thanks. Answer You can try changing const tx = new Tx(txObject); to const
Unable to deploy Solidity contract to Rinkeby network (Invalid asm.js: Invalid member of stdlib)
I’ve been learning Solidity using this course by Stephen Grider and it’s been going well until now, where I am trying to deploy my code to the Rinkeby test network. For reference, I am using Node version 11.15.0 with npm version 6.7.0 with these dependencies: I have spent hours switching between versions of Node.js, npm, and all sorts of combinations
Call Function From Solidity With Web3
I am having trouble calling a simple function from my solidity contract. Here’s how the code is structured so far: In my web3Api.js file I have: Then in my projectApi.js file I have: Note: When I call the global variable throughout this file it successfully returns all my contract’s functions So this next part is where I’m running into trouble.
calling smart contracts methods using web3 ethereum
Trying to work around the blockchain using Ethereum, I’m facing problems when trying to interface with a deployed contract. What I would try to achieve is to call a method to display information added to a private blockchain deployed locally using Geth. I can’t call any function from my smart contract and I’ve been wondering if I’m doing something wrong…