Book Image

Solidity Programming Essentials

Book Image

Solidity Programming Essentials

Overview of this book

Solidity is a contract-oriented language whose syntax is highly influenced by JavaScript, and is designed to compile code for the Ethereum Virtual Machine. Solidity Programming Essentials will be your guide to understanding Solidity programming to build smart contracts for Ethereum and blockchain from ground-up. We begin with a brief run-through of blockchain, Ethereum, and their most important concepts or components. You will learn how to install all the necessary tools to write, test, and debug Solidity contracts on Ethereum. Then, you will explore the layout of a Solidity source file and work with the different data types. The next set of recipes will help you work with operators, control structures, and data structures while building your smart contracts. We take you through function calls, return types, function modifers, and recipes in object-oriented programming with Solidity. Learn all you can on event logging and exception handling, as well as testing and debugging smart contracts. By the end of this book, you will be able to write, deploy, and test smart contracts in Ethereum. This book will bring forth the essence of writing contracts using Solidity and also help you develop Solidity skills in no time.
Table of Contents (17 chapters)
Title Page
Copyright and Credits
Packt Upsell
Contributors
Preface
Index

The do...while loop


The do...while loop is very similar to the while loop. The general form of a do...while loop is as follows:

Declare and Initialize a counter
do {
Execute the instructions here
Increment the value of counter
} while(check the value of counter using an expression or condition)

There is a subtle difference between the while and do...while loops. If you notice, the condition in do...while is placed towards the end of the loop instructions. The instructions in the while loop is not executed at all if the condition is false; however, the instruction in the do...while loop get executed once, before the condition is evaluated. So, if you want to execute the instructions at least once, the do...while loop should be preferred compared to the while loop. Take a look at the following screenshot of a code snippet: