Ethereum JS source code

1. Eth is a kind of digital token of Ethereum, which is regarded as "bitcoin version 2.0". It adopts the blockchain technology "Ethereum", which is different from bitcoin. It is an open-source public blockchain platform with intelligent contract results, and a resonance network composed of tens of thousands of computers around the world. Developers need to pay eth to support the application. Like other digital currencies, ether currency can be bought and sold on the trading platform

warm tips: the above explanations are for reference only, without any suggestions. There are risks in entering the market, so investment should be cautious. Before making any investment, you should make sure that you fully understand the nature of the investment and the risks involved in the proct. After a detailed understanding and careful evaluation of the proct, you can judge whether to participate in the transaction
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2. At the top of Ethereum is DAPP. It exchanges with the smart contract layer through Web3. JS. All smart contracts run on EVM (Ethereum virtual machine) and use RPC calls. Below EVM and RPC are the four core contents of Ethereum, including: blockchain, consensus algorithm, mining and network layer. Except DAPP, all other parts are in the Ethereum client. The most popular Ethereum client is geth (go Ethereum)

3.

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

4. What does it mean that there is no verification of the display in the browser and the release contract code? He certainly didn't have time to do it.

5. Eth is a kind of digital token of Ethereum. Developers need to pay eth to support the application. Ether currency, like other digital currencies, can be bought and sold on the trading platform
generally speaking, Ethereum is an open source platform, digital currency and blockchain platform, which provides developers with a platform to build on the blockchain

6. Ethereum source code

7. 1. Preparation. Windows 64 bit system, C disk to reserve a certain space, download and install vs2015 (the official note only supports vs2015, to be verified), cmake I use 3.10.1, the system language to non Unicode language, such as English (U.S.), otherwise there will be errors in the final compilation
2. Project clone to local, project address:
3. Execute submole updata -- init
4. Install script in the directory_ Deps.bat is copied to the root directory and executed. This step will download hunter, boost, libjson, etc. to Disk C, which takes a long time. Please wait patiently
5. Go to the directory of the project and create the build subdirectory,

8. The Internet has just begun, intelligent life coming