ConditionChecks Smart Contract

Overview

The ConditionChecks smart contract demonstrates the use of Solidity's require(), assert(), and revert() statements. These statements are essential for controlling the flow of the contract, ensuring that certain conditions are met, and handling errors in a robust manner.

Features

• Set Value: Users can set a value that must be greater than zero.
• Double Value: The value can be doubled, with an internal check to prevent overflow.
• Reset Value: The owner of the contract can reset the value to zero.

Functions

1. setValue(uint256 _value)

Sets the value variable to the input _value.

• Parameters:

  • _value: A uint256 number that must be greater than zero.

• Require Condition:

  • The function uses require() to ensure _value is greater than zero.
  • If the condition is not met, the transaction is reverted with the error message "Value must be greater than zero".

2. doubleValue()

Doubles the current value stored in the contract.

• Assert Condition:
  • The function uses assert() to check that doubling the value does not cause an overflow.
  • If the assertion fails, the transaction is reverted.

3. resetValue()

Resets the value variable to zero. Only the owner of the contract can perform this action.

• Revert Condition:
  • The function uses revert() to stop the execution and revert the transaction if the caller is not the contract owner.
  • The error message returned is "Only the owner can reset the value".

Deployment

To deploy the ConditionChecks contract:

1. Install a development environment like Remix or use tools like Truffle or Hardhat.
2. Compile the contract with a Solidity compiler version ^0.8.0.
3. Deploy the contract to your preferred Ethereum network.

Usage

Set a Value

contractInstance.setValue(10);

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

contract ConditionChecks {
    uint256 public value;
    address public owner;

    constructor() {
        owner = msg.sender;
    }

    function setValue(uint256 _value) public {
        require(_value > 0, "Value must be greater than zero");
        value = _value;
    }

    function doubleValue() public {
        uint256 doubledValue = value * 2;
        assert(doubledValue / 2 == value);

        value = doubledValue;
    }

    function resetValue() public {
        if (msg.sender != owner) {
            revert("Only the owner can reset the value");
        }

        value = 0;
    }
}