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}
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Houselease.sol
 
Houselease.sol
 
pragma solidity ^0.4.0;
 
pragma solidity ^0.4.0;
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RenterT.sol
 
RenterT.sol
 
pragma solidity ^0.4.22;
 
pragma solidity ^0.4.22;
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TenantT.sol
 
TenantT.sol
 
pragma solidity ^0.4.22;
 
pragma solidity ^0.4.22;

2021年2月26日 (五) 18:54的版本

EXAMPLE

Loan contract 

  Loan contract, refers to a contract where a lender delivers a certain amount of funds to a borrower, and the latter returns the same amount of funds within a certain period of time and pays interests to the lender. There are 6 terms in the contract that consists of two aspects:
   1) the borrower shall submit a loan application stating the amount he/she wants to borrow, and
   2) the lender may deposit funds into the contract account until the target of loan is reached. Before borrowing, the contract requires that the borrower must confirm the loan information and check the historical loan records, and then calculate the corresponding interests. Meanwhile, the contract asserts that the borrower pays off the loan amount before the loan date comes.

Auction contract 

  Auction contract involves two parties: auctioneer who is an enterprise legal person engaged in auction activities, and bidders who are some citizens, legal persons or organizations to participate in bidding for auction targets. The highest bidding process is described as the following steps. The auctioneer starts the auction system after setting a reserve price and an auction end time, and waits for the auction to end; The bidders can bid anytime during the system. If the bid is greater than the current highest price, the system records it as new highest price, puts the bid into the fund pool, and returns the bid paid by the previous highest bidder; otherwise, the bidder fails and the bid is returned; After the auction time is over, the auctioneer can collect the highest bid from the fund pool.

House-leasing contract 

  House-leasing contract, takes assets as the transaction subject between lessor and lessee. There are 7 terms in the contract, including two aspects:
  1) the lessor can register the house after depositing the rental deposit, and 
  2) the lessee can keep the right to use the house during the leasing period after depositing the rent. After confirming the leased house, the contract requires that the lessee shall pay the rent, and the lessor must transfer the right to the lessee within one week. Meanwhile, the contract stipulates the pre-condition for the lessor to charge the rent paid by the lessee, and the postcondition for both parties to get their deposits back after the house inspection.

HouseLease.scs
contract Houselease{
	party Renter{
		registerHouse()
		collectRent()
		collectBail()
		transferHouse()
		checkHouse()
	}
	
	party Tenant{
		confirmLease(endLeasingDuration:Date,
			payDuration:Date)
		payRent()
		returnHouse()
		collectBail()
	}
	
	house : House
	infos : contractInfo
	
	term term1 : Renter can registerHouse
		while deposit $infos::renterBail.
		
	term term2 : Tenant can confirmLease
		when after Renter did registerHouse
		while deposit $infos::tenantBail
		where infos::startLeasingTime = now and
			infos::endLeasingTime = endLeasingDuration + now
			and infos::payDate = payDuration + now
			and infos::payDuration = payDuration.
			
	term term3 : Renter must transferHouse
		when within 7 day after Tenant did confirmLease
		while deposit $ house::useRight.
	
	term term4 : Tenant must payRent
		when before Tenant did confirmLease		
		while deposit $infos::rental
			withdraw $house::useRight
		where infos::payDate = infos::payDate + infos::payDuration
			and infos::totalRental = infos::totalRental + infos::rental.
	
	term term5 : Renter can collectRent
		while withdraw $infos::totalRental
		where infos::totalRental = 0.
	
	term term6 : Tenant must returnHouse
		when within 7 day after Renter did checkHouse
		while deposit $house::useRight
			transfer $house::useRight to Renter.
	
	term term7_1 : Renter can collectBail
		when within 15 day after Renter did checkHouse
		while withdraw $infos::renterBail.
	
	term term7_2 : Tenant can collectBail
		when within 15 day after Renter did checkHouse
		while withdraw $infos::tenantBail.
		
		type contractInfo {
			renterBail : Money
			tenantBail : Money
			rental : Money
			totalRental : Money
			penalty : Money
			startLeasingTime : Date
			endLeasingTime : Date
			payDate : Date
			payDuration : Date
		}
		
		type House {
			ownershipNumber : integer
			location : String
			area : integer
			usage : String
			price : Money
			useRight : String
			usufruct : String
			dispositionRight : String
			possessionRight : String
		}
}

Houselease.sol
pragma solidity ^0.4.0;
		
import "./RenterT.sol";
import "./TenantT.sol";

contract Houselease {
	
	RenterT Renter;
	TenantT Tenant;
	
	House house;
	contractInfo infos;
	
	uint start;
	struct contractInfo{
		uint renterBail;
		uint tenantBail;
		uint rental;
		uint totalRental;
		uint penalty;
		uint startLeasingTime;
		uint endLeasingTime;
		uint payDate;
		uint payDuration;
	}
	struct House{
		uint ownershipNumber;
		bytes32 location;
		uint area;
		bytes32 usage;
		uint price;
		uint useRight;
		uint usufruct;
		uint dispositionRight;
		uint possessionRight;
	}
	
	function Houselease(){
		start = now;
		Renter = new RenterT();
		Tenant = new TenantT();
	}

	modifier onlyRenter{
		require(Renter.contains(msg.sender));
		_;
	}
	
	modifier onlyTenant{
		require(Tenant.contains(msg.sender));
		_;
	}
	
	modifier term2Modifier{
		require(now > Renter.registerHouseTime());
		require(infos.tenantBail > 0);
		_;
	}
	
	modifier term3Modifier{
		require((now > Tenant.confirmLeaseTime()) &&(now < Tenant.confirmLeaseTime()+604800));
		require(house.useRight > 0);
		_;
	}
	
	modifier term4Modifier{
		require(now < Tenant.confirmLeaseTime());
		require(infos.rental > 0);
		_;
	}
	
	modifier term6Modifier{
		require((now > Renter.checkHouseTime()) &&(now < Renter.checkHouseTime()+604800));
		require(house.useRight > 0);
		_;
	}
	
	modifier term7_1Modifier{
		require((now > Renter.checkHouseTime()) &&(now < Renter.checkHouseTime()+1296000));
		_;
	}
	
	modifier term7_2Modifier{
		require((now > Renter.checkHouseTime()) &&(now < Renter.checkHouseTime()+1296000));
		_;
	}
	
	function registerHouse() onlyRenter() public payable {
		//USER CODE HERE
		//CHECK
	
	}
	
	function confirmLease(uint endLeasingDuration, uint payDuration) onlyTenant() term2Modifier() public payable {
		//USER CODE HERE
		infos.startLeasingTime = now;
		infos.endLeasingTime = endLeasingDuration + now;
		infos.payDate = payDuration + now;
		infos.payDuration = payDuration;
		//CHECK
		assert(infos.startLeasingTime == now && (infos.endLeasingTime == endLeasingDuration + now && (infos.payDate == payDuration + now && infos.payDuration == payDuration)));
	}
	
	function transferHouse() onlyRenter() term3Modifier() public payable {
		//USER CODE HERE
		//CHECK
	
	}
	
	function payRent() onlyTenant() term4Modifier() public payable {
		//USER CODE HERE
		infos.payDate = infos.payDate + infos.payDuration;
		infos.totalRental = infos.totalRental + infos.rental;
		msg.sender.transfer(house.useRight);
		//CHECK
		assert(infos.payDate == infos.payDate + infos.payDuration && infos.totalRental == infos.totalRental + infos.rental);
	}
	
	function collectRent() onlyRenter() term7_1Modifier() public payable {
		//USER CODE HERE
		infos.totalRental = 0;
		msg.sender.transfer(infos.totalRental);
		//CHECK
		assert(infos.totalRental == 0);
	}
	
	function returnHouse() onlyTenant() term6Modifier() public payable {
		//USER CODE HERE
		address(Renter).transfer(house.useRight);
		//CHECK
	
	}
	
}

RenterT.sol
pragma solidity ^0.4.22;

contract RenterT{
	
	
	//attributes of actionregisterHouse
	bool _isregisterHouseDone;
	uint _registerHouseTime;
	
	//attributes of actioncollectRent
	bool _iscollectRentDone;
	uint _collectRentTime;
	
	//attributes of actioncollectBail
	bool _iscollectBailDone;
	uint _collectBailTime;
	
	//attributes of actiontransferHouse
	bool _istransferHouseDone;
	uint _transferHouseTime;
	
	//attributes of actioncheckHouse
	bool _ischeckHouseDone;
	uint _checkHouseTime;
	
	uint _max;
	bool _isRenterDone;
	uint _i;
	
	address[] _RenterAddress;
	function RenterT(){
		_max = now*1000;
	}
	
	function regist(address a) public {
		_RenterAddress[_i] = a;
		_i++;
	}
	
	function getAddress(uint _i) public returns (address a){
		return _RenterAddress[_i];
	}
	
	function registerHouseDone(address a){
		_registerHouseTime = now;
		_isRenterDone = true;
	}
	
	function registerHouseTime() returns (uint result){
	    if(_isregisterHouseDone){
	        return _registerHouseTime;
	    }
	    return _max;
	}
	
	function collectRentDone(address a){
		_collectRentTime = now;
		_isRenterDone = true;
	}
	
	function collectRentTime() returns (uint result){
	    if(_iscollectRentDone){
	        return _collectRentTime;
	    }
	    return _max;
	}
	
	function collectBailDone(address a){
		_collectBailTime = now;
		_isRenterDone = true;
	}
	
	function collectBailTime() returns (uint result){
	    if(_iscollectBailDone){
	        return _collectBailTime;
	    }
	    return _max;
	}
	
	function transferHouseDone(address a){
		_transferHouseTime = now;
		_isRenterDone = true;
	}
	
	function transferHouseTime() returns (uint result){
	    if(_istransferHouseDone){
	        return _transferHouseTime;
	    }
	    return _max;
	}
	
	function checkHouseDone(address a){
		_checkHouseTime = now;
		_isRenterDone = true;
	}
	
	function checkHouseTime() returns (uint result){
	    if(_ischeckHouseDone){
	        return _checkHouseTime;
	    }
	    return _max;
	}
	
	function contains(address a) returns (bool result) {
	    for (uint _j = 0; _j < _RenterAddress.length; _j++ ) {  //for loop example
            if (a == _RenterAddress[_j]){
                return true;
            }         
      }
      return false;
	}
	
}

TenantT.sol
pragma solidity ^0.4.22;

contract TenantT{
	
	
	//attributes of actionconfirmLease
	bool _isconfirmLeaseDone;
	uint _confirmLeaseTime;
	
	//attributes of actionpayRent
	bool _ispayRentDone;
	uint _payRentTime;
	
	//attributes of actionreturnHouse
	bool _isreturnHouseDone;
	uint _returnHouseTime;
	
	//attributes of actioncollectBail
	bool _iscollectBailDone;
	uint _collectBailTime;
	
	uint _max;
	bool _isTenantDone;
	uint _i;
	
	address[] _TenantAddress;
	function TenantT(){
		_max = now*1000;
	}
	
	function regist(address a) public {
		_TenantAddress[_i] = a;
		_i++;
	}
	
	function getAddress(uint _i) public returns (address a){
		return _TenantAddress[_i];
	}
	
	function confirmLeaseDone(address a){
		_confirmLeaseTime = now;
		_isTenantDone = true;
	}
	
	function confirmLeaseTime() returns (uint result){
	    if(_isconfirmLeaseDone){
	        return _confirmLeaseTime;
	    }
	    return _max;
	}
	
	function payRentDone(address a){
		_payRentTime = now;
		_isTenantDone = true;
	}
	
	function payRentTime() returns (uint result){
	    if(_ispayRentDone){
	        return _payRentTime;
	    }
	    return _max;
	}
	
	function returnHouseDone(address a){
		_returnHouseTime = now;
		_isTenantDone = true;
	}
	
	function returnHouseTime() returns (uint result){
	    if(_isreturnHouseDone){
	        return _returnHouseTime;
	    }
	    return _max;
	}
	
	function collectBailDone(address a){
		_collectBailTime = now;
		_isTenantDone = true;
	}
	
	function collectBailTime() returns (uint result){
	    if(_iscollectBailDone){
	        return _collectBailTime;
	    }
	    return _max;
	}
	
	function contains(address a) returns (bool result) {
	    for (uint _j = 0; _j < _TenantAddress.length; _j++ ) {  //for loop example
            if (a == _TenantAddress[_j]){
                return true;
            }         
      }
      return false;
	}
	
}

Purchase contract 

  Purchase contract, transfers the ownership of goods from a seller to a buyer through logistics company. There are 10 terms in the contract, including three parts: 
  1) once the goods are confirmed, the seller will sign a contract and take twice the contracting price as the delivery price, 
  2) the goods are sent to the buyer through logistics when the buyer purchases the goods, and 3) only when the logistics successfully delivers the goods to the buyer can the seller get back the payment. According to relevant laws, the contract requires the buyer can apply for compensation if goods do not arrive within 10 days after payment, or the seller can automatically confirm the arrival if the buyer does not confirm or apply for refund within 7 days after arrival.

purchase.scs
contract Purchase{
	party seller{
		//定义seller角色，有四个动作
		create()
		abort()
		confirmClaim()
		autoConfirm()
	}

	party buyer{
		confirmPurchase()//
		confirmReceived()
		overtimeClaim()
		claim()
		revokeClaim()
	}
	
	party logistics{
		//第三方角色，物流公司
		arrive()
	}

	balance : integer

	xxxDescription : goods//定义一个商品描述，good是下面定义的商品结构体
	
	term no1 : seller can create 
		while deposit $ xxxDescription::price*2.
	//卖家可以创建合约，同时要存入物品两倍价格作为保证金
	
	term no2 : buyer can confirmPurchase 
		when after seller did create 
		while deposit $ xxxDescription::price*2.
	//买家创建合约后买家可以确认购买，同时要存入物品两倍价格作为保证金和货款
	
	term no3 : seller can abort 
		when before buyer did confirmPurchase 
		while withdraw $ xxxDescription::price*2.
	//卖家在买家确认购买之前，可以撤回合约，并取走两倍的保证金
	
	term no4 : logistics must arrive 
		when within 10 day after buyer did confirmPurchase.
	//买家付款后10天内必须到货
	
	term no5 : buyer must confirmReceived 
		when within 7 day after logistics did arrive
		while
			withdraw $ xxxDescription::price
			transfer $ balance to seller.
	//买家在到货后7天内必须确认到货，同时双方取走保证金，卖家取走货款
	
	term no6 : buyer can claim 
		when within 7 day after logistics did arrive.
	//买家可以在到货7天内申请赔款
		
	term no7 : buyer can overtimeClaim 
		when after start + 10 day or after logistics did arrive.
	//如果货物在付款后10天内没到，买家可以申请赔款
	
	term no8 : seller can confirmClaim 
		when after buyer did claim or after buyer did overtimeClaim
		while transfer $ balance to buyer.
	//卖家可以同意退款，并把所有保证金及货款转给买家
	
	term no9 : buyer can revokeClaim 
		when after buyer did claim or after buyer did overtimeClaim
		while
			withdraw $ xxxDescription::price
			transfer $ balance to seller.
	//买家可以撤回退款申请
		
	term no10 : seller can autoConfirm 
		when before buyer did claim and 7 day after logistics did arrive
		while
			withdraw $ xxxDescription::price
			transfer $ balance to seller.
	//如果到货七天内买家没有确认或申请退款，卖家可以自动确认到货。
	
	type goods {
		name : Name//物品名称
		quantity : integer//物品数量
		price : Money//价格
		package : String//运送包装
	}
}

buyerT.sol
pragma solidity ^0.4.22;

contract buyerT{
	
	
	//attributes of actionconfirmPurchase
	bool _isconfirmPurchaseDone;
	uint _confirmPurchaseTime;
	
	//attributes of actionconfirmReceived
	bool _isconfirmReceivedDone;
	uint _confirmReceivedTime;
	
	//attributes of actionovertimeClaim
	bool _isovertimeClaimDone;
	uint _overtimeClaimTime;
	
	//attributes of actionclaim
	bool _isclaimDone;
	uint _claimTime;
	
	//attributes of actionrevokeClaim
	bool _isrevokeClaimDone;
	uint _revokeClaimTime;
	
	uint _max;
	bool _isbuyerDone;
	uint _i = 0;
	
	address[] _buyerAddress;
	function buyerT(){
		_max = now*1000;
	}
	
	function regist(address a) public {
		_buyerAddress[_i] = a;
		_i++;
	}
	
	function getAddress() public returns (address a){
		return _buyerAddress[_i];
	}
	
	function confirmPurchaseDone(address a){
		_confirmPurchaseTime = now;
		_isbuyerDone = true;
	}
	
	function confirmPurchaseTime() returns (uint result){
	    if(_isconfirmPurchaseDone){
	        return _confirmPurchaseTime;
	    }
	    return _max;
	}
	
	function confirmReceivedDone(address a){
		_confirmReceivedTime = now;
		_isbuyerDone = true;
	}
	
	function confirmReceivedTime() returns (uint result){
	    if(_isconfirmReceivedDone){
	        return _confirmReceivedTime;
	    }
	    return _max;
	}
	
	function overtimeClaimDone(address a){
		_overtimeClaimTime = now;
		_isbuyerDone = true;
	}
	
	function overtimeClaimTime() returns (uint result){
	    if(_isovertimeClaimDone){
	        return _overtimeClaimTime;
	    }
	    return _max;
	}
	
	function claimDone(address a){
		_claimTime = now;
		_isbuyerDone = true;
	}
	
	function claimTime() returns (uint result){
	    if(_isclaimDone){
	        return _claimTime;
	    }
	    return _max;
	}
	
	function revokeClaimDone(address a){
		_revokeClaimTime = now;
		_isbuyerDone = true;
	}
	
	function revokeClaimTime() returns (uint result){
	    if(_isrevokeClaimDone){
	        return _revokeClaimTime;
	    }
	    return _max;
	}
	
	function contains(address a) returns (bool result) {
	    for (uint _j = 0; _j < _buyerAddress.length; _j++ ) {  //for loop example
            if (a == _buyerAddress[_j]){
                return true;
            }         
      }
      return false;
	}
	
}

logisticsT.sol
pragma solidity ^0.4.22;

contract logisticsT{
	
	
	//attributes of actionarrive
	bool _isarriveDone;
	uint _arriveTime;
	
	uint _max;
	bool _islogisticsDone;
	uint _i = 0;
	
	address[] _logisticsAddress;
	function logisticsT(){
		_max = now*1000;
	}
	
	function regist(address a) public {
		_logisticsAddress[_i] = a;
	}
	
	function getAddress() public returns (address a){
		return _logisticsAddress[_i];
	}
	
	function arriveDone(address a){
		_arriveTime = now;
		_islogisticsDone = true;
	}
	
	function arriveTime() returns (uint result){
	    if(_isarriveDone){
	        return _arriveTime;
	    }
	    return _max;
	}
	
	function contains(address a) returns (bool result) {
	    for (uint _j = 0; _j < _logisticsAddress.length; _j++ ) {  //for loop example
            if (a == _logisticsAddress[_j]){
                return true;
            }
      }
      return false;
	}
	
}

Purchase.sol
pragma solidity ^0.4.0;
		
import "./sellerT.sol";
import "./buyerT.sol";
import "./logisticsT.sol";

contract Purchase {
	
	sellerT seller;
	buyerT buyer;
	logisticsT logistics;
	
	uint balance;
	goods xxxDescription;
	
	uint start;
	struct goods{
		bytes32 name;
		uint quantity;
		uint price;
		bytes32 package;
	}
	
	function Purchase(){
		start = now;
		seller = new sellerT();
		buyer = new buyerT();
		logistics = new logisticsT();
	}

	modifier onlyseller{
		require(seller.contains(msg.sender));
		_;
	}
	
	modifier onlybuyer{
		require(buyer.contains(msg.sender));
		_;
	}
	
	modifier onlylogistics{
		require(logistics.contains(msg.sender));
		_;
	}
	
	modifier no2Modifier{
		require(now > seller.createTime());
		require(xxxDescription.price * 2 > 0);
		_;
	}
	
	modifier no3Modifier{
		require(now < buyer.confirmPurchaseTime());
		_;
	}
	
	modifier no4Modifier{
		require((now > buyer.confirmPurchaseTime()) &&(now < buyer.confirmPurchaseTime()+864000));
		_;
	}
	
	modifier no5Modifier{
		require((now > logistics.arriveTime()) &&(now < logistics.arriveTime()+604800));
		_;
	}
	
	modifier no6Modifier{
		require((now > logistics.arriveTime()) &&(now < logistics.arriveTime()+604800));
		_;
	}
	
	modifier no7Modifier{
		require(now > start + 864000 || now > logistics.arriveTime());
		_;
	}
	
	modifier no8Modifier{
		require(now > buyer.claimTime() || now > buyer.overtimeClaimTime());
		_;
	}
	
	modifier no9Modifier{
		require(now > buyer.claimTime() || now > buyer.overtimeClaimTime());
		_;
	}
	
	modifier no10Modifier{
		require(now < buyer.claimTime() && now > logistics.arriveTime()+604800);
		_;
	}
	
	function create() onlyseller() public payable {
		//USER CODE HERE
		//CHECK
	
	}
	
	function confirmPurchase() onlybuyer() no2Modifier() public payable {
		//USER CODE HERE
		//CHECK
	
	}
	
	function abort() onlyseller() no3Modifier() public payable {
		//USER CODE HERE
		msg.sender.transfer(xxxDescription.price * 2);
		//CHECK
	
	}
	
	function arrive() onlylogistics() no4Modifier() public {
		//USER CODE HERE
		//CHECK
	
	}
	
	function confirmReceived() onlybuyer() no5Modifier() public payable {
		//USER CODE HERE
		msg.sender.transfer(xxxDescription.price);
		address(seller).transfer(balance);
		//CHECK
	
	}
	
	function claim() onlybuyer() no6Modifier() public {
		//USER CODE HERE
		//CHECK
	
	}
	
	function overtimeClaim() onlybuyer() no7Modifier() public {
		//USER CODE HERE
		//CHECK
	
	}
	
	function confirmClaim() onlyseller() no8Modifier() public payable {
		//USER CODE HERE
		address(buyer).transfer(balance);
		//CHECK
	
	}
	
	function revokeClaim() onlybuyer() no9Modifier() public payable {
		//USER CODE HERE
		msg.sender.transfer(xxxDescription.price);
		address(seller).transfer(balance);
		//CHECK
	
	}
	
	function autoConfirm() onlyseller() no10Modifier() public payable {
		//USER CODE HERE
		msg.sender.transfer(xxxDescription.price);
		address(seller).transfer(balance);
		//CHECK
	
	}
	
}

sellerT.sol
pragma solidity ^0.4.22;

contract sellerT{
	
	
	//attributes of actioncreate
	bool _iscreateDone;
	uint _createTime;
	
	//attributes of actionabort
	bool _isabortDone;
	uint _abortTime;
	
	//attributes of actionconfirmClaim
	bool _isconfirmClaimDone;
	uint _confirmClaimTime;
	
	//attributes of actionautoConfirm
	bool _isautoConfirmDone;
	uint _autoConfirmTime;
	
	uint _max;
	bool _issellerDone;
	uint _i = 0;
	
	address[] _sellerAddress;
	function sellerT(){
		_max = now*1000;
	}
	
	function regist(address a) public {
		_sellerAddress[_i] = a;
		_i++;
	}
	
	function getAddress() public returns (address a){
		return _sellerAddress[_i];
	}
	
	function createDone(address a){
		_createTime = now;
		_issellerDone = true;
	}
	
	function createTime() returns (uint result){
	    if(_iscreateDone){
	        return _createTime;
	    }
	    return _max;
	}
	
	function abortDone(address a){
		_abortTime = now;
		_issellerDone = true;
	}
	
	function abortTime() returns (uint result){
	    if(_isabortDone){
	        return _abortTime;
	    }
	    return _max;
	}
	
	function confirmClaimDone(address a){
		_confirmClaimTime = now;
		_issellerDone = true;
	}
	
	function confirmClaimTime() returns (uint result){
	    if(_isconfirmClaimDone){
	        return _confirmClaimTime;
	    }
	    return _max;
	}
	
	function autoConfirmDone(address a){
		_autoConfirmTime = now;
		_issellerDone = true;
	}
	
	function autoConfirmTime() returns (uint result){
	    if(_isautoConfirmDone){
	        return _autoConfirmTime;
	    }
	    return _max;
	}
	
	function contains(address a) returns (bool result) {
	    for (uint _j = 0; _j < _sellerAddress.length; _j++ ) {  //for loop example
            if (a == _sellerAddress[_j]){
                return true;
            }         
      }
      return false;
	}
	
}
取自“https://www.smartlegalcontract.cn/mediawiki/index.php?title=INVALID-TITLE&oldid=356”