pragma solidity ^0.4.10;//枚舉類型 contract enumTest{enum ActionChoices{Left,Right,Straight,Still}// 0 1 2 3//input/output uint ActionChoices public _choice;ActionChoices defaultChoice = ActionChoices.Straight;function setStraight(ActionChoices choice) public{_choice = choice;}function getDefaultChoice() constant public returns(uint){return uint(defaultChoice); //2 }function isLeft(ActionChoices choice) constant public returns(bool){if (choice == ActionChoices.Left){return true; //0 }return false; //1,2,3 } } //構(gòu)造函數(shù) contract StructTest{struct Student{string name;uint sex;uint age;//uint year =15;ParserError: Expected ';' but got '=':Cannot be assigned within the constructor,unless use constructor public{} }Student public std1 = Student('lily',0,15);Student public std2 = Student({name:'lin',sex:1,age:17});/*0: string: name lin1: uint256: sex 12: uint256: age 17*/Student [] public students;function assgin() public{students.push(std1);students.push(std2);std1.name ='eilinge';/*0: string: name eilinge1: uint256: sex 02: uint256: age 15*/} }//映射/字典 contract mappingTest{mapping(uint => string) id_names;/*mapping (_key => _values)鍵的類型允許除映射外的所有類型,如數(shù)組、合約、枚舉、結(jié)構(gòu)體.值的類型無限制.映射可以被視作一個哈希表,其中所有可能的鍵已被虛擬化的創(chuàng)建,被映射到一個默認值(二進制表示的零)在映射表中,我們并不存儲建的數(shù)據(jù),僅僅儲存它的keccak256哈希值,用來查找值時使用。映射類型,僅能用來定義狀態(tài)變量,或者是在內(nèi)部函數(shù)中作為storage類型的引用*/constructor() public{id_names[0x001] = 'jim';//構(gòu)造函數(shù)內(nèi)聲明的全局變量,任意函數(shù)都可以進行調(diào)用id_names[0x002] = 'eilin';}function getNamebyId(uint id) constant public returns(string){string name = id_names[id]; //局部變量 name,僅能在本函數(shù)內(nèi)使用,其他函數(shù)無法進行調(diào)用return name;} }//修改器 pragma solidity ^0.4.10;contract modifierTest{address owner=msg.sender;uint public v3;modifier onlyowner(address own) {require(own == owner);_;}function setv3() onlyowner(msg.sender) {v3 = 10;} }

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轉(zhuǎn)載于:https://www.cnblogs.com/eilinge/p/9959372.html

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