pragma solidity >=0.4.22 <0.7.0; contract AttendanceRegister { struct Student{ string name; uint class; } event Added(string name, uint class, uint time); mapping(uint => Student) public register; // roll number => student details function add(uint rollNumber, string memory name, uint class) public returns (uint256){ require(class > 0 && class <= 12, "Invalid class"); require(register[rollNumber].class == 0, "Roll number not available"); Student memory s = Student(name, class); register[rollNumber] = s; emit Added(name, class, now); return rollNumber; } function getStudentName(uint rollNumber) public view returns (string memory) { return register[rollNumber].name; } }
0.6.1