December 2018
Intermediate to advanced
222 pages
6h 6m
English
Content preview from Blockchain Quick Start Guide
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Access restriction
Access restriction is a solidity security pattern. It only allows authorized parties to access certain functions. Due to the public nature of the blockchain, all data on the blockchain is visible to anyone. It is critical to declare your contract function, state with restricted access control, and provide security against unauthorized access to smart contract functionality.
pragma solidity ^0.4.24;contract Ownable { address owner; uint public initTime = now; constructor() public { owner = msg.sender; } //check if the caller is the owner of the contract modifier onlyOwner { require(msg.sender == owner,"Only Owner Allowed." ); _; } //change the owner of the contract //@param _newOwner the address of the new owner of the ...Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
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I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.