我正在通过此https://medium.com/coinmonks/ethereum-land-marketplace-dapp-tutorial-part-tutorial-part-part-1-create-and-ande-and-and-and-deploy-a--Smart-Contract-351BC0D62BE2
下面有一个函数,我不知道余额[所有者]和余额[plot.owner]。
function buyPlot(uint index) public payable {
Plot storage plot = plots[index];
require(msg.sender != plot.owner && plot.forSale && msg.value >= plot.price);
if(plot.owner == 0x0) {
balances[owner] += msg.value;
}else {
balances[plot.owner] += msg.value;
}
plot.owner = msg.sender;
plot.forSale = false;
emit PlotOwnerChanged(index);
}
这是否意味着,如果没有人拥有该地块(plot.owner == 0x0),然后将资金支付给智能合约的所有者(创建者)或土地的第一所有者?
这是整个代码。
pragma solidity ^0.4.11;
contract LandContract {
address owner;
mapping (address => uint) public balances;
struct Plot {
address owner;
bool forSale;
uint price;
}
Plot[12] public plots;
event PlotOwnerChanged(
uint index
);
event PlotPriceChanged(
uint index,
uint price
);
event PlotAvailabilityChanged(
uint index,
uint price,
bool forSale
);
constructor() public {
owner = msg.sender;
plots[0].price = 4000;
plots[0].forSale = true;
plots[1].price = 4000;
plots[1].forSale = true;
plots[2].price = 4000;
plots[2].forSale = true;
plots[3].price = 4000;
plots[3].forSale = true;
plots[4].price = 4000;
plots[4].forSale = true;
plots[5].price = 4000;
plots[5].forSale = true;
plots[6].price = 4000;
plots[6].forSale = true;
plots[7].price = 4000;
plots[7].forSale = true;
plots[8].price = 4000;
plots[8].forSale = true;
plots[9].price = 4000;
plots[9].forSale = true;
plots[10].price = 4000;
plots[10].forSale = true;
plots[11].price = 4000;
plots[11].forSale = true;
}
function putPlotUpForSale(uint index, uint price) public {
Plot storage plot = plots[index];
require(msg.sender == plot.owner && price > 0);
plot.forSale = true;
plot.price = price;
emit PlotAvailabilityChanged(index, price, true);
}
function takeOffMarket(uint index) public {
Plot storage plot = plots[index];
require(msg.sender == plot.owner);
plot.forSale = false;
emit PlotAvailabilityChanged(index, plot.price, false);
}
function getPlots() public view returns(address[], bool[], uint[]) {
address[] memory addrs = new address[](12);
bool[] memory available = new bool[](12);
uint[] memory price = new uint[](12);
for (uint i = 0; i < 12; i++) {
Plot storage plot = plots[i];
addrs[i] = plot.owner;
price[i] = plot.price;
available[i] = plot.forSale;
}
return (addrs, available, price);
}
function buyPlot(uint index) public payable {
Plot storage plot = plots[index];
require(msg.sender != plot.owner && plot.forSale && msg.value >= plot.price);
if(plot.owner == 0x0) {
balances[owner] += msg.value;
}else {
balances[plot.owner] += msg.value;
}
plot.owner = msg.sender;
plot.forSale = false;
emit PlotOwnerChanged(index);
}
function withdrawFunds() public {
address payee = msg.sender;
uint payment = balances[payee];
require(payment > 0);
balances[payee] = 0;
require(payee.send(payment));
}
function destroy() payable public {
require(msg.sender == owner);
selfdestruct(owner);
}
}
是的,plot.owner
是拥有情节的人。而owner
是部署合同的人。您可以将其视为尚未购买的任何情节属于owner
,即部署合同的人(假设他没有将所有权转移给其他任何人),那么当您购买不属于的财产时以前由任何人拥有的,这笔钱将交给合同的所有者