Read and Write to Smart Contract

So far, we were only reading information from Smart Contracts, but not writing. It’s time we actually write something!

Video

💡Watch the video first, then try it yourself!

View the Full Course Now 

Contract

We’re going to expand our Smart Contract from before and add a function to write!

//SPDX-License-Identifier: MIT
 
pragma solidity 0.8.13;
 
contract MyContract {
    string public myString = "Hello world";
 
    function updateOurString(string memory _myString) public {
        myString = _myString;
    }
}
 

Open in Remix 

Interaction

If you deploy the Smart Contract to the JavaScript VM, you’ll see that a new button appeared in a different color:

You can also uncollapse the input field:

When you enter

1. “Hello Earth” in the input field and
2. send off the transaction, then
3. a new Transaction will appear in the log windows and
4. The string “myString” is updated to “Hello Earth”

Next Step

Now that you know how to interact with a Smart Contract, its time to do something more meaningful with our newly gained knowledge. But before that, let me summarize what we learned in the next lecture real quick…