Use Ethereum to rack one's brains

1.

If you want to query the transaction records on the main network, you can use Etherscan. However, if you build your own private chain, how should you query the transaction records

the answer is that you need to listen to the logs on the chain, save them in the database, and then query them in the database. For example:

< pre t = "code" L = "Java" > varaddr = & quot& quot;< br />varfilter=web3.eth.filter({fromB lock:0 ,toBlock:' latest', address:addr });< br />filter.get(function(err,transactions){
transactions.forEach(function(tx){
vartxInfo=web3.eth.getTransaction(tx.transactionHash);
/ / at this time, the transaction information txinfo can be stored in the database
})< br />});

Web3. Eth. Filter() is used to monitor the log on the chain, and Web3. Eth. Gettransaction() is used to extract the information of the specified transaction. Once the transaction information is obtained, it can be stored in the database for query

recommend a practical introction, you can see: Ethereum tutorial

2. Like bitcoin, Ethernet currency not only circulates and trades all over the world, but also has different prices on various trading platforms
in this way, there is a price spread and arbitrage space!

3. First of all, you need to understand what Ethereum is. Ethereum is a platform and a programming language that enables developers to build and release the next generation of distributed applications. Ethereum can be used to program, distribute, guarantee and trade anything: voting, domain names, financial exchanges, crowdfunding, corporate governance, contracts and most agreements, intellectual property, and smart assets that benefit from hardware integration. Eth is a kind of digital token of Ethereum. Developers need to pay eth to support the application.

4. What the platform does is the price spread trading of eth (ether currency) on various trading platforms all over the world. It uses a variety of trading strategies to match and trade between currencies, such as ether currency / bitcoin, ether currency / US dollar, and other counterfeit currencies. On the basis of professional investment management of ethtrade, it can make your investment increase up to 25% per month.

5. Ethereum currency has been recognized all over the world. As for the trade you mentioned, I don't know if it is a chance to speculate or circle money. You can discuss it in private.

6. It is recommended that celletf be a decentralized trading platform. Celletf is a comprehensive application platform (celletf. IO). Relying on the deployment of Ethereum public chain, including a number of smart contracts / protocols, passive quotation mechanism and ETF's primary and secondary al market architecture, celletf can embrace the infinite possibility of defi with only one site.

7. Contract code of Ethereum. If the WPS document is used to analyze the , it's not clear.
I haven't touched it

8. I think the Internet has increased the regulation of digital currency. It is understood that whether in wechat group or online post bar, there are many kinds of virtual currency business, such as matchmaking, app development, currency issuance, and even people contracting these businesses, forming a one-stop instrial chain. Another business disclosed that the leverage ratio of virtual currency related contract transactions can reach up to 500 times. And the blockchain is the latest one; The instrial revolution;. However, it is undeniable that there are many & lt; Smart people;, Under the banner of blockchain, we are engaged in all kinds of activities; Illegal money taking; Activities.