如何處理函式選擇器的元組？

元組類型如何編碼到函式簽名中以生成 4 字節函式選擇器？官方規範沒有說明元組類型的任何內容。

用於(type1,type2,...)表示結構。

例如0x 2.0fillOrder中的函式：

function fillOrder(
   Order memory order,
   uint256 takerAssetFillAmount,
   bytes memory signature
)
   public
   returns (LibFillResults.FillResults memory fillResults);

struct Order {
   address makerAddress;           // Address that created the order.      
   address takerAddress;           // Address that is allowed to fill the order. If set to 0, any address is allowed to fill the order.          
   address feeRecipientAddress;    // Address that will recieve fees when order is filled.      
   address senderAddress;          // Address that is allowed to call Exchange contract methods that affect this order. If set to 0, any address is allowed to call these methods.
   uint256 makerAssetAmount;       // Amount of makerAsset being offered by maker. Must be greater than 0.        
   uint256 takerAssetAmount;       // Amount of takerAsset being bid on by maker. Must be greater than 0.        
   uint256 makerFee;               // Amount of ZRX paid to feeRecipient by maker when order is filled. If set to 0, no transfer of ZRX from maker to feeRecipient will be attempted.
   uint256 takerFee;               // Amount of ZRX paid to feeRecipient by taker when order is filled. If set to 0, no transfer of ZRX from taker to feeRecipient will be attempted.
   uint256 expirationTimeSeconds;  // Timestamp in seconds at which order expires.          
   uint256 salt;                   // Arbitrary number to facilitate uniqueness of the order's hash.     
   bytes makerAssetData;           // Encoded data that can be decoded by a specified proxy contract when transferring makerAsset. The last byte references the id of this proxy.
   bytes takerAssetData;           // Encoded data that can be decoded by a specified proxy contract when transferring takerAsset. The last byte references the id of this proxy.
}

函式選擇器使用以下公式計算：

fillOrder((address,address,address,address,uint256,uint256,uint256,uint256,uint256,uint256,bytes,bytes),uint256,bytes)

這會產生一個 keccak256 : b4be83d519a652e54a6073d7e55643f575508112b09dcc74264b807477b576c5，前 4 個字節是：b4be83d5

您可以通過查看這個名為 fillOrder 的 tx 來確認這一點：https ://etherscan.io/tx/0x4811b7492bd845a46a052b063f943c4760174e932cb171ca25a934de6e7e4da4

引用自：https://ethereum.stackexchange.com/questions/50010