Itération 122442
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1 answers
2 votes
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Address.transfer(amount); What does it mean? who is recipient?
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7 votes

address someone = msg.sender; someone.transfer(10); msg.sender refers to the sender of the transaction/call. address someone = msg.sender; Means that we store the sender address in the someone ...

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3 answers
1 votes
4k views
How to build and sign a transaction to deploy a contract
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7 votes

Got it working with the following method: First, get the contract instance without specifying an address (according to documentation, it is optional): let abi = JSON.parse(fs.readFileSync(tokenAbi)....

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1 answers
3 votes
3k views
How to sign a send method in web3 1.0?
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5 votes

First, you need to generate your transaction, here is an example: let tx_builder = contractInstance.methods.myMethod(arg1, arg2, ...); let encoded_tx = tx_builder.encodeABI(); let ...

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2 answers
4 votes
1k views
Block header format
4 votes

You can find the block header's structure in the Yellow paper, 4.4 (page 5). I don't have time to go through eveyrthing, but if I do not make any mistake, for example, you could bind the following: ...

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1 answers
1 votes
331 views
Geth light node returns 0 pending / queued transactions despite being fully synced. Cannot reasonably access tx-pool data
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3 votes

If my source still applies, light node cannot maintain a pool of pending transactions (except its own transactions). A light client only maintains its own transactions. It cannot maintain a pool of ...

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4 answers
25 votes
28k views
What is a chainID in Ethereum, how is it different than NetworkID, and how is it used?
3 votes

- How is it different than networkID? It is not. chainID is a different name but refers to the same thing. - Is chainID and networkID needed in every block or just the genesis block? This is ...

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1 answers
0 votes
2k views
Remove an ERC20 contract from blockchain so it won't be visible in etherscan
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3 votes

If you had implemented the selfdestruct function, it would have been possible. But if you have not, then there is nothing to do. Pro tip => Use testnet(s)!

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1 answers
-5 votes
297 views
Need Code to create ethereum wallet address
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3 votes

You should have a look at : bitcore-mnemonic ethereum-bip44 ethereumjs-wallet However, as said in the comments, this question is too broad. Try it, and come back with specific questions.

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1 answers
3 votes
2k views
Is it possible that the same address sends out two transactions at the same time
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3 votes

Then does this indicate that the same address can NOT send two transactions at the same time? No. It indicates that you cannot send two transaction with the same nonce from the same address. As the ...

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2 answers
0 votes
427 views
IP address and system details of msg.sender
2 votes

I do not think it is possible. At least, it cannot be found in the documentation: https://solidity.readthedocs.io/en/v0.6.1/miscellaneous.html#index-4 Moreover, it would be a major paradox into a ...

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1 answers
1 votes
491 views
Transfer data using solidity transfer function
2 votes

To transfer data from contract A to contract B, you do not use transfer function. transfer is meant to transfer ether. But if you want to transfer, lets say an integer, from contract A to contract B, ...

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1 answers
1 votes
2k views
How to queue up simultaneous signed transactions
2 votes

You can use batch request, it allows you to send in a specific order transactions: http://web3js.readthedocs.io/en/1.0/web3-eth.html?highlight=batch#batchrequest

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1 answers
0 votes
42 views
Creating a token that allows the owner to take a proportion as fee?
2 votes

This code is just an example, I made it fast, the order may not be correct. However, your question is a very basic code logic, not something really related to ethereum itself or solidity. You may try ...

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5 answers
15 votes
8k views
Using web3 to sign a transaction without connecting to geth
2 votes

It is possible to sign transaction with web3js, check the 1.0.0 version

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2 answers
0 votes
531 views
Does an ethereum address exist on all networks when created?
2 votes

Address are not really created. They exists since the very beginning of the chain. However, people claim ownership of addresses. For example, when you create a wallet in myetherwallet, you don't ...

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1 answers
1 votes
1k views
Should I use smart contract for storing huge data and real-time updates?
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2 votes

If you end needing storing lot of data in smart contract, it means you don't understand what it is made for. Storing data in a smart contract is crazy expensive in gas because you change the EVM ...

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1 answers
0 votes
524 views
Transferring tokens to hardcoded addresses
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2 votes

In my opinion, the best way is to make a function that takes an array of addresses as a parameter: Solidity function: function foo(address[] add, int value) public { for (int i = 0; i <= add....

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1 answers
1 votes
14 views
Can a blockchain only store transaction proofs or any kind of data in it?
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1 votes

No time to write a very complete answer, but here is the basics: Storing data in blockchain has the following disadvantages: Increase the data that needs to be stored by the chain. But as everyone ...

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1 answers
0 votes
15 views
Listen for events without knowing the contract address
1 votes

What you are asking is similar to try to listen for any person saying "Hello !" from every phone number that is used. But back to the question, I have not practiced for a long time, but I ...

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1 answers
2 votes
264 views
how to run a private blockchain network with geth on other machines, such as server and client?
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1 votes

Based on this comment: i want to run multiple nodes on different machines with the same genesis.json To run multiple nodes, you have two solutions: Solution one: Static nodes One your second (or ...

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1 answers
0 votes
2k views
How to Open console In geth 1.9.10
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1 votes

Using geth attach, you need to provide the IP:PORT Example: geth attach 'http://localhost:8501' Your geth must provide RPC interface with something like this in the geth execution command: --rpc --...

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1 answers
0 votes
329 views
What is nodekey of bootnode command?
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1 votes

Bootnodes must be identified by an enode. Enodes are derived from private key. Full quote: Each ethereum node, including a bootnode is identified by an enode identifier. These identifiers are ...

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2 answers
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110 views
Tokens & Smart Contract "Upgrade"
1 votes

Yes. You can implement a simple logic in your contract for that: For example: mapping(address => bool) public hacker; function doSomething() public { require(!hacker[...

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1 answers
0 votes
33 views
Receiving unexpected JSONRPC requests on my website
1 votes

To quickly answer the question, it does not seem to be something bad. The second request seem to be requesting block data based on its number . I am not sure for the first. It seems to be ...

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1 answers
0 votes
591 views
Metamask (Chrome extension) web3.js console: ETH transaction issue (synchronous methods) + web3.version
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1 votes

The answer to your first question seems to be quite straight forward: you need to provide a callback to the function. It is what the error tells you to do, moreover, the documentation says a callback ...

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2 answers
1 votes
257 views
web3 - function returning new contract's address
1 votes

If you use getTransactionreceipt, then you can use the contractAddress property. getTransactionReceipt(hash, function(error, result) { console.log("address = " + result.contractAddress); }); ...

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1 answers
0 votes
324 views
Incorrect Usage. flag needs an argument: -rpcaddr = Ethereum private blockchain
1 votes

According to documentation (haven't practice for a while) --rpcaddr value HTTP-RPC server listening interface (default: "localhost") You need to pass the address on witch one your rpc ...

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1 answers
0 votes
254 views
API to get transactions between 2 blocks in Ethereum
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1 votes

You can use web3.js. In web3, you can get blocks You can also get transaction from block I let you check all the other functions available.

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1 answers
0 votes
99 views
What is saved on every block on Ethereum?
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1 votes

The information you are looking for are ALL in the yellow/white paper, it would take too long to explain everything here and its already explained in the yellow paper A block, exactly like in bitcoin,...

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1 answers
0 votes
184 views
Using web3js apis for ethereum transactions
1 votes

Yes check this It is always a security risk if you share your private key. But in some cases you need to. You need to be more specific about your "security" in order to answer correctly this.

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