solidity get contract address issue

Question

    // SPDX-License-Identifier: MIT
pragma solidity >=0.7.0 < 0.9.0;
contract Receiver{
    
    function getAddress() public view returns(address){
        return address(this);
    }
  
}

contract Caller{
    Receiver receiver;
    constructor(){
        receiver = new Receiver();
    }

    function getAddress() public view returns(address){
        return receiver.getAddress();
    }
  
}

My question is: when testing the above code on Remix, I couldn't get the same address, why? here is the ss: many thanks!

Answer 1

Here is the catch: The new keyword deploys and creates a new contract instance. in Caller's contract's constructor you are actually deploying a new instance of Receiver. I add another function to get the deployed Receiver instance

contract Caller{
    Receiver receiver;
    constructor(){
        // you created a new Receiver instance
        receiver = new Receiver();
    }
    // By calling this you are not interacting with the Receiver instance that you separately deployed on Remix.
    // this interacts with the Receiver instance which is deployed in the constructor
    function getAddress() public view returns(address){
        return receiver.getAddress();
    }
    // this returns the address of deployed Receiver instance 
    function deployedReceiverAddress() public view returns(address){
        return address(receiver);
    }
}

you do not have to deploy Receiver contract on remix. Caller will already deploy a new contract. in the above both functions in Caller returns same result: