ethereum(以太坊)(九)--global(全局函數)

pragma solidity ^0.4.0;

contract modifierTest{
    bytes32 public blockhash;
    address public coinbase;
    uint public difficulty;
    uint public gaslimit;
    uint public blockNum;
    uint public timestamp;
    bytes public calldata1;
    uint public gas;
    address public sender;
    bytes4 public sig;
    uint public msgValue;
    uint public now1;
    uint public gasPrice;
    address public txOrigin;


    function tt(){
        //給定區塊號的哈希值,只支持最近256個區塊,且不包含當前區塊
        blockhash = block.blockhash(block.number -1);
        coinbase  = block.coinbase;//當前塊礦工的地址
        difficulty = block.difficulty;//當前塊的難度
        gaslimit = block.gaslimit;//當前塊的gaslimit
        blockNum = block.number; //當前區塊的塊號
        timestamp = block.timestamp;//當前塊的時間戳==now
        calldata1 = msg.data;//完整的調用數據: 0x1e36169e
        gas = msg.gas;//當前還剩下的gas
        sender = msg.sender;//當前調用發起人的地址: 0xCA35b7d915458EF540aDe6068dFe2F44E8fa733c
        sig = msg.sig;//調用數據的前4個字節(函數標識符): 0x1e36169e
        msgValue = msg.value;//這個消息所攜帶的貨幣量,單位wei
        now1 = now;
        gasPrice = tx.gasprice;//交易的gas價格
        txOrigin = tx.origin;//交易的發送者(完整的調用鏈): 0xCA35b7d915458EF540aDe6068dFe2F44E8fa733c
    }
}

直接調用,後面無需()

• abi.encode(...) returns (bytes):對給定的參數進行ABI編碼。
• abi.encodePacked(...) returns (bytes): Performes packed encoding of the given arguments
• abi.encodeWithSelector(bytes4 selector, ...) returns (bytes)::對給定的參數進行ABI編碼——從第二個預置給定的四字節選擇器開始
• abi.encodeWithSignature(string signature, ...) returns (bytes):至關於abi.encodeWithSelector(bytes4(keccak256(signature), ...)
• block.blockhash(uint blockNumber) returns (bytes32): 給定的塊的hash值, 只有最近工做的256個塊的hash值—— 在 0.4.22 後請使用blockhash(uint blockNumber).
• block.coinbase (address): 當前塊的礦工的地址
• block.difficulty (uint): 當前塊的難度
• block.gaslimit (uint): 當前塊的gaslimit
• block.number (uint):當前塊的數量
• block.timestamp (uint):當前塊的時間戳
• gasleft() returns (uint256): 剩餘 gas
• msg.data(bytes): 完整的calldata
• msg.gas(uint): 剩餘 gas - 0.4.21後請使用 gasleft()
• msg.sender (address): 消息的發送者（當前調用）
• msg.value (uint): 和消息一塊兒發送的wei的數量
• now (uint): 當前塊的時間戳（block.timestamp的別名）
• tx.gasprice (uint):交易的gas價格
• tx.origin (address):交易的發送者（全調用鏈）
• assert(bool condition): abort execution and revert state changes if condition is false (用於內部錯誤)
• require(bool condition): abort execution and revert state changes if condition is false (用於輸入錯誤或外部組件的錯誤)
• require(bool condition, string message): abort execution and revert state changes if condition is false (用於輸入錯誤或外部組件的錯誤). 並提供錯誤信息.
• revert(): 停止執行並還原狀態更改
• revert(string message):停止執行並還原狀態更改，提供解釋字符串
• blockhash(uint blockNumber) returns (bytes32): : 給定的塊的hash值, 只有最近工做的256個塊的hash值
• keccak256(...) returns (bytes32):計算（緊湊排列的）參數的 Ethereum-SHA3 hash值
• sha3(...) returns (bytes32): an alias to keccak256
• sha256(...) returns (bytes32): 計算（緊湊排列的）參數的SHA256 hash值
• ripemd160(...) returns (bytes20):計算 256個（緊湊排列的）參數的RIPEMD
• ecrecover(bytes32 hash, uint8 v, bytes32 r, bytes32 s) returns (address): 橢圓曲線簽名公鑰恢復，錯誤時返回0
• addmod(uint x, uint y, uint k) returns (uint): compute (x + y) % k where the addition is performed with arbitrary precision and does not wrap around at 2**256. Assert that k != 0 starting from version 0.5.0.
• mulmod(uint x, uint y, uint k) returns (uint): compute (x * y) % k where the multiplication is performed with arbitrary precision and does not wrap around at 2**256. Assert that k != 0 starting from version 0.5.0.
• this (current contract’s type): 當前合約，在地址上顯式轉換
• super: 在層次關係上一層的合約
• selfdestruct(address recipient): 銷燬當前的合約，將其資金髮送到指定address
• suicide(address recipient): a deprecated alias to selfdestruct
• <address>.balance (uint256): address地址中的帳戶餘額（以wei爲單位）
• <address>.send(uint256 amount) returns (bool): 將必定量wei發送給address地址，若失敗返回false。
• <address>.transfer(uint256 amount): 將必定量wei發送給address地址，若失敗拋出異常。