gskapka
  • Member for 3 years, 6 months
  • Last seen more than 1 year ago
I need to know how to send ether from one address to another address for my Dapp
5 votes

Okay big edit now you've clarified: In order to send given amounts to given addresses successfully via a smart-contract, you can have a Sender.sol that looks like the following: pragma solidity 0.5....

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ERC20 Contract - OpenZeppelin - total confusion
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3 votes

Also included in the library is a couple of examples - you can find them in their github repo. One, called SimpleToken looks like this: pragma solidity ^0.4.24; import "../token/ERC20/ERC20.sol"; /*...

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How to limit N bytes to value range using Oraclize Ledger-Proof Random Number -- unfair raffle
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3 votes

So your solution of discarding the numbers is known as rejection sampling and is indeed the way to solve your issue for your given inputs. As you've also noticed, there is a cost associated with this ...

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Generating and signing a transaction - what am I doing wrong?
3 votes

Your raw transaction before the first RLP encoding needs the chain ID in place of the empty v value per EIP155. Then afterwards, you replace the v with (chainID << 1) + 35, and the r & s ...

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What is the v part of transaction signature?
2 votes

Your r here is calculated as the X co-ord of some point R % the curve order n. Due to the nature of the curve, there are however 4 valid points that could all have this X co-ord, and so the v is used ...

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Chainlink Kaleido Contract compilation
2 votes

Whilst I can't help specifically with those errors, I can help with creating a smart-contract that gets the current price of ETH in USD using Oraclize per the comment on your question: pragma ...

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Can i change data in a database using smart contract and oraclize?
2 votes

You certainly can achieve such a thing via Oraclize! First you'll need to create and expose and API to perform the database duties you need. Next you'll need to use the Oraclize compuatation ...

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Explain "_term" Variable And What Is Slot In This Contract
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2 votes

It appears that term here means "length of time from now". The contract is locking up tokens for any given term, and it appears that the number of different "lockings" a single account can achieve ...

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Oraclize callback is not called with more data in it
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2 votes

Oraclize employee here, and looking at your code with a __callback I'm pretty sure the Oracle you are referring to is indeed Oraclize, so hopefully I can help! :p   Without seeing the rest of ...

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How accurate are Etherscan's internal tx's on Rinkeby for Oraclize calls?
2 votes

Disclosure: am an Oraclize employee.   There includes in the Oraclize API a helper function called oraclize_getPrice. It expects two parameters, the first is the data-source you are querying, ...

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Emit not firing event more than once
1 votes

Your update function appears to only consume your event once: export const update = (callback) => { contract.LoggingString((error, result) => callback(error, result)); } Once the callback ...

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Oraclize a restfullAPI using a specific number represented by the variable z
Accepted answer
1 votes

Meta: You should edit your original question to include the screenshots that you have mistakenly posted as a reply. You should refrain from posting images of code, and post the actual code instead. ...

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I want to oraclize this smartcontract to get some output on a localhost. I am desperate what should i do?
1 votes

You contract & Oraclize implementation looks good so far, however your __callback function isn't doing anything since you've commented out the line which sets the contract's global variable z. ...

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CallBack function is not triggerring
1 votes

User Rick Park is very close with his answer, in that there is a problem is in the first line of your __callback function. You appear to have both a require that checks the wrong variabel, & it's ...

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Truffle migration with contract argument
1 votes

You can either deploy setting a variable to the contract instance via await, or neater still, use the .then method of the promise to chain the deployments, giving you access to the instance (and so ...

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How do I define my token to pass truffle test?
1 votes

The top line of your javascript is wrong. You've called the artifact DappToken but tried to instantiate it with xyzToken, which isn't defined, and hence the error you're getting. Also, consider ...

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Wait until smart contract function executes before continuing to loop
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0 votes

If your web3 call is returning a promise you can simply await it: async function doThing() { //... const result = await web3call() if(!result){ // Do whatever... } }

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How to rewrite my transfer transaction?
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0 votes

It will overwrite your previous transaction, and due to the higher gas price, hopefully will get mined sooner! MyEtherWallet provide a tool to do just this, though you'll need your original ...

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ERC-20 Token Transfer Error : Bad jump destination
0 votes

Your code is the javascript you've used to generate & sign the transaction, but the error is a solidity error. And it is very likely due to the fact that your contract address is 0x55, which is ...

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Compiling error when using .value() for sending money between contracts using solidity and truffle framework
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0 votes

You were very close, you just need a slight change in the syntax of your external contract function call in your addToBalence(...) [sic] function: //... function addToBalence(string name, uint amount)...

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How to store a function return in a variable?
Accepted answer
0 votes

You're concatenating your string correctly, all you need to do now is call that function wherever it is you need it:   function update() payable { newOraclizeQuery("Oraclize query was sent....

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Oraclize parity error
0 votes

There must be something stopping geth from retrieving the contract from the github source. Instead, you can manually copy and paste the oraclizeAPI_0.5.sol contract from here into your file, above ...

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Transferring an ERC-20 using web3js 1.0.0
0 votes

Web3 1.0 isn't actually released yet, which might be why you're having some issues. See the disclaimer here. Instead, use the API docs here to craft your transactions. And since you added a question ...

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Ways to Decentralize Oraclize
0 votes

By leveraging the proof-types Oraclize offer (about which see here in the docs) you can ameliorate much of the centralizing aspect of using an oracle service. This means that now you're only trusting ...

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