Blockchain Quick Start Guide

Modifiers

In solidity, the modifier is used to change the behavior of a function. They can automatically check a condition prior to executing the function. Here is an example, as follows:

pragma solidity ^0.4.24;contract Modifiers {         address public admin;    function construct () public {       admin = msg.sender;    }    //define the modifiers    modifier onlyAdmin() {        // if a condition is not met then throw an exception        if (msg.sender != admin) revert();        // or else just continue executing the function        _;    }    // apply modifiers    function kill() onlyAdmin public {         selfdestruct(admin);    }}