如何判斷一個地址是合約還是只是一個可靠的地址

我的 Solidity 合約允許使用者從他們持有的代幣中賺取利息。我想阻止持有我的代幣的合約賺取利息。這將阻止 pancakeswap 路由器或任何其他路由器或合約賺取利息。

我目前看不到任何方法可以從可靠程式碼中做到這一點。

嘗試使用<address>.code(bytes memory) 或<address>.codehash(bytes32) - 理論上，它們不應該為合約為空。

您可以使用Address.solOpenZeppelin 提供的庫，如果特定地址是合約地址，則方法checkIfContract將返回，否則：true``false

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Address.sol)

pragma solidity ^0.8.0;

/**
* @dev Collection of functions related to the address type
*/
library Address {
   /**
    * @dev Returns true if `account` is a contract.
    *
    * [IMPORTANT]
    * ====
    * It is unsafe to assume that an address for which this function returns
    * false is an externally-owned account (EOA) and not a contract.
    *
    * Among others, `isContract` will return false for the following
    * types of addresses:
    *
    *  - an externally-owned account
    *  - a contract in construction
    *  - an address where a contract will be created
    *  - an address where a contract lived, but was destroyed
    * ====
    *
    * [IMPORTANT]
    * ====
    * You shouldn't rely on `isContract` to protect against flash loan attacks!
    *
    * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
    * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
    * constructor.
    * ====
    */
   function isContract(address account) internal view returns (bool) {
       // This method relies on extcodesize/address.code.length, which returns 0
       // for contracts in construction, since the code is only stored at the end
       // of the constructor execution.

       return account.code.length > 0;
   }

   /**
    * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
    * `recipient`, forwarding all available gas and reverting on errors.
    *
    * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
    * of certain opcodes, possibly making contracts go over the 2300 gas limit
    * imposed by `transfer`, making them unable to receive funds via
    * `transfer`. {sendValue} removes this limitation.
    *
    * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
    *
    * IMPORTANT: because control is transferred to `recipient`, care must be
    * taken to not create reentrancy vulnerabilities. Consider using
    * {ReentrancyGuard} or the
    * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
    */
   function sendValue(address payable recipient, uint256 amount) internal {
       require(address(this).balance >= amount, "Address: insufficient balance");

       (bool success, ) = recipient.call{value: amount}("");
       require(success, "Address: unable to send value, recipient may have reverted");
   }

   /**
    * @dev Performs a Solidity function call using a low level `call`. A
    * plain `call` is an unsafe replacement for a function call: use this
    * function instead.
    *
    * If `target` reverts with a revert reason, it is bubbled up by this
    * function (like regular Solidity function calls).
    *
    * Returns the raw returned data. To convert to the expected return value,
    * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
    *
    * Requirements:
    *
    * - `target` must be a contract.
    * - calling `target` with `data` must not revert.
    *
    * _Available since v3.1._
    */
   function functionCall(address target, bytes memory data) internal returns (bytes memory) {
       return functionCall(target, data, "Address: low-level call failed");
   }

   /**
    * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
    * `errorMessage` as a fallback revert reason when `target` reverts.
    *
    * _Available since v3.1._
    */
   function functionCall(
       address target,
       bytes memory data,
       string memory errorMessage
   ) internal returns (bytes memory) {
       return functionCallWithValue(target, data, 0, errorMessage);
   }

   /**
    * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
    * but also transferring `value` wei to `target`.
    *
    * Requirements:
    *
    * - the calling contract must have an ETH balance of at least `value`.
    * - the called Solidity function must be `payable`.
    *
    * _Available since v3.1._
    */
   function functionCallWithValue(
       address target,
       bytes memory data,
       uint256 value
   ) internal returns (bytes memory) {
       return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
   }

   /**
    * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
    * with `errorMessage` as a fallback revert reason when `target` reverts.
    *
    * _Available since v3.1._
    */
   function functionCallWithValue(
       address target,
       bytes memory data,
       uint256 value,
       string memory errorMessage
   ) internal returns (bytes memory) {
       require(address(this).balance >= value, "Address: insufficient balance for call");
       require(isContract(target), "Address: call to non-contract");

       (bool success, bytes memory returndata) = target.call{value: value}(data);
       return verifyCallResult(success, returndata, errorMessage);
   }

   /**
    * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
    * but performing a static call.
    *
    * _Available since v3.3._
    */
   function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
       return functionStaticCall(target, data, "Address: low-level static call failed");
   }

   /**
    * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
    * but performing a static call.
    *
    * _Available since v3.3._
    */
   function functionStaticCall(
       address target,
       bytes memory data,
       string memory errorMessage
   ) internal view returns (bytes memory) {
       require(isContract(target), "Address: static call to non-contract");

       (bool success, bytes memory returndata) = target.staticcall(data);
       return verifyCallResult(success, returndata, errorMessage);
   }

   /**
    * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
    * but performing a delegate call.
    *
    * _Available since v3.4._
    */
   function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
       return functionDelegateCall(target, data, "Address: low-level delegate call failed");
   }

   /**
    * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
    * but performing a delegate call.
    *
    * _Available since v3.4._
    */
   function functionDelegateCall(
       address target,
       bytes memory data,
       string memory errorMessage
   ) internal returns (bytes memory) {
       require(isContract(target), "Address: delegate call to non-contract");

       (bool success, bytes memory returndata) = target.delegatecall(data);
       return verifyCallResult(success, returndata, errorMessage);
   }

   /**
    * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
    * revert reason using the provided one.
    *
    * _Available since v4.3._
    */
   function verifyCallResult(
       bool success,
       bytes memory returndata,
       string memory errorMessage
   ) internal pure returns (bytes memory) {
       if (success) {
           return returndata;
       } else {
           // Look for revert reason and bubble it up if present
           if (returndata.length > 0) {
               // The easiest way to bubble the revert reason is using memory via assembly

               assembly {
                   let returndata_size := mload(returndata)
                   revert(add(32, returndata), returndata_size)
               }
           } else {
               revert(errorMessage);
           }
       }
   }
}

contract TestContract {
   using Address for address;

   function checkIfContract(address _address) public view returns(bool) {
       return _address.isContract();
   }
}

引用自：https://ethereum.stackexchange.com/questions/117541