Tipe Nilai
uint, address, bool, bytes
Tipe Nilai adalah pelajaran Web3 & DApp Development Fundamentals gratis di CoddyKit. Ini adalah pelajaran 1 dari 4. Kamu bisa membaca pelajaran lengkapnya di bawah secara gratis — lalu praktikkan langsung di browser dengan editor kode bawaan dan tutor AI 24/7. Ini adalah bagian dari jalur belajar Web3 & DApp Development Fundamentals, dan progresmu tersinkronisasi di web dan aplikasi CoddyKit. Kursus Web3 & DApp Development Fundamentals mencakup 4 pelajaran total.
Bagian dari pelajaran ini belum diterjemahkan dan ditampilkan dalam bahasa Inggris.
What Are Value Types?
Value types in Solidity hold their data directly and are copied whenever they are assigned to a variable or passed to a function.
This is different from reference types (arrays, structs, mappings) which point to a shared location. Value types include bool, integers, address, and fixed-size bytes.
- Always copied on assignment
- Stored compactly
- Predictable gas cost
Booleans
The bool type holds either true or false. It is the result of comparison and logical operators.
Solidity supports ! (not), && (and), || (or). Logical operators short-circuit, just like in most languages.
<code>bool isActive = true;
bool hasPaid = false;
bool ready = isActive && !hasPaid;</code>Unsigned Integers
uint stores non-negative whole numbers. uint is an alias for uint256.
You can choose smaller sizes in steps of 8 bits: uint8, uint16, ... up to uint256. Smaller types can save storage when packed together in a struct.
<code>uint256 balance = 1000;
uint8 smallCount = 255; // max value for uint8</code>Signed Integers
int stores values that can be negative or positive. int is an alias for int256.
An int8 ranges from -128 to 127. Use signed integers only when negatives are genuinely possible, since they are easy to misuse.
<code>int256 temperature = -15;
int8 delta = 100;</code>Overflow Protection
Since Solidity 0.8.0, arithmetic automatically reverts on overflow and underflow. You no longer need SafeMath for basic safety.
If you intentionally want wrapping behavior for gas savings, wrap the math in an unchecked block.
<code>uint8 x = 255;
// x + 1 would revert (overflow)
unchecked {
x = x + 1; // wraps to 0
}</code>The address Type
An address holds a 20-byte Ethereum account identifier. It can refer to a wallet (EOA) or a contract.
The address type exposes members like .balance (in wei) and methods such as .transfer() and .send().
<code>address owner = 0x5B38Da6a701c568545dCfcB03FcB875f56beddC4;
uint256 bal = owner.balance;</code>address vs address payable
A plain address cannot receive Ether directly. To send funds you need address payable, which adds .transfer() and .send().
You convert between them explicitly with payable(addr).
<code>address recipient = msg.sender;
address payable wallet = payable(recipient);
wallet.transfer(1 ether);</code>Fixed-Size Bytes
Solidity offers fixed-size byte arrays from bytes1 to bytes32. These are value types and are cheaper than dynamic bytes when the length is known.
They are useful for hashes, identifiers, and short fixed data.
<code>bytes32 hash = keccak256(abi.encodePacked('hello'));
bytes1 firstByte = hash[0];</code>Enums
An enum defines a custom type with a fixed set of named constants. Internally each value is a small uint starting at 0.
Enums make state machines readable, such as the status of an order.
<code>enum Status { Pending, Shipped, Delivered }
Status public current = Status.Pending;
function ship() public {
current = Status.Shipped;
}</code>Literals and Units
Solidity provides handy unit suffixes. Ether units: wei, gwei, ether. Time units: seconds, minutes, hours, days, weeks.
1 ether equals 10**18 wei.
<code>uint256 fee = 1 ether; // 1000000000000000000 wei
uint256 timeout = 2 days; // 172800 seconds</code>Default Values
Solidity has no null. Every value type has a zero default: uint is 0, bool is false, address is the zero address 0x0...0.
Checking against the zero address is a common guard.
<code>address public admin; // defaults to address(0)
function setAdmin(address a) public {
require(a != address(0), 'zero address');
admin = a;
}</code>Quick Check
Test your understanding of Solidity value types.
Recap
You learned the core value types in Solidity:
boolfor true/false logicuint/intwith built-in overflow protection since 0.8.0addressandaddress payablefor accounts and transfers- Fixed
bytesN,enum, and unit literals like1 ether
Remember: value types are copied, and every type has a zero default value.
Pertanyaan yang Sering Diajukan
Apakah pelajaran “Tipe Nilai” gratis?
Ya — teks lengkap “Tipe Nilai” gratis dibaca di sini di web. Untuk praktiknya secara interaktif (editor kode bawaan dan tutor AI 24/7) dan buka sisa kursus Web3 & DApp Development Fundamentals, upgrade ke CoddyKit PRO. Kursus Web3 & DApp Development Fundamentals mencakup 4 pelajaran total.
Apa yang akan aku pelajari di “Tipe Nilai”?
uint, address, bool, bytes Kamu berlatih Web3 & DApp Development Fundamentals dengan kode praktik yang langsung kamu jalankan di browser, dan tutor AI 24/7 menjawab pertanyaanmu saat kamu mengerjakan pelajaran ini.
Apakah aku perlu pengalaman untuk memulai Web3 & DApp Development Fundamentals?
Tidak diperlukan pengalaman sebelumnya. Web3 & DApp Development Fundamentals di CoddyKit dirancang untuk pemula hingga pelajar tingkat lanjut, jadi kamu bisa memulai di sini atau dari awal dan belajar sesuai kecepatan kamu sendiri. Ini adalah pelajaran 1 dari 4.
Berapa lama pelajaran “Tipe Nilai” memakan waktu?
Sebagian besar pelajaran CoddyKit memakan waktu sekitar 5–10 menit. Setiap pelajaran ringkas dan interaktif, jadi kamu membuat kemajuan stabil dan melanjutkan dari tempat kamu tinggalkan di web dan aplikasi.
Bisakah aku menulis dan menjalankan kode dalam pelajaran Web3 & DApp Development Fundamentals ini?
Ya. Setiap pelajaran Web3 & DApp Development Fundamentals menyertakan editor kode bawaan, jadi kamu menulis dan menjalankan kode nyata langsung di browser dan mendapatkan umpan balik AI instan — tidak diperlukan penyiapan lokal.