在Solidity中导入和加载源文件

将外部文件加载到Remix中有两个主要原因：

导入库或依赖项（对于您不会编辑的文件）
to load some files for manipulation and editing (for files you might want to edit)

导入库或依赖项

When importing from npm, or a URL (like GitHub, an IPFS gateway, or a Swarm gateway) you do not need to do anything more than use the import statement in your contract. The dependencies do not need to be "preloaded" into the File Explorer's current Workspace before the contract is compiled.

Files loaded from the import statement are placed in the File Explorer's current Workspace's .deps folder.

Under the hood, Remix checks to see if the files are already loaded in the .deps directory. If not, it gets them via unpkg if it is an npm lib.

以下是一些示例import语句：

Import from npm

Use an npm package name directly in the import path. Remix resolves the package automatically via unpkg.

import "@openzeppelin/contracts/token/ERC20/ERC20.sol";

import "@openzeppelin/contracts@4.2.0/token/ERC20/ERC20.sol";

备注

In the scoped-package example above, @openzeppelin is the name of the npm library. In the following example the library's name does not begin with an @ - but Remix will go and check npm for a library of that name.

import "solidity-linked-list/contracts/StructuredLinkedList.sol";

Import from a GitHub URL

Paste a full GitHub URL to import a file directly from a public repository.

import "https://github.com/OpenZeppelin/openzeppelin-contracts/blob/v2.5.0/contracts/math/SafeMath.sol";

You should specify the release tag (where available), otherwise you will get the latest code in the main branch. For OpenZeppelin Contracts you should only use code published in an official release, the example above imports from OpenZeppelin Contracts v2.5.0.

从 Swarm 导入

Use a bzz-raw:// URI to import a file stored on the Swarm decentralized storage network.

import 'bzz-raw://5766400e5d6d822f2029b827331b354c41e0b61f73440851dd0d06f603dd91e5';

从 IPFS 导入

Use an ipfs:// URI to import a file stored on the IPFS network.

import 'ipfs://Qmdyq9ZmWcaryd1mgGZ4PttRNctLGUSAMpPqufsk6uRMKh';

导入不在 .deps 中的本地文件

要导入不在.deps文件夹中的文件，请使用相对路径（./）。例如：

import "./myLovelyLovelyLib.sol";

警告

Imports cannot reference files in a different Workspace. Both the contract and its dependencies must be in the same Workspace.

从计算机的文件系统导入文件

This method uses Remix Desktop, which has direct access to your computer's filesystem. Open the folder you want to work with from within the Remix Desktop app and its files will appear in the File Explorer.

导入文件以进行操作。

When importing from the home tab widgets or with a remix command in the console, the files are placed in the root of the current Workspace inside a folder that shows their source - eg GitHub or gists.

在 Remix 主页选项卡上的导入按钮

The Gist, GitHub, Swarm, IPFS, & HTTPS buttons are to assist in getting files into Remix so you can explore.

点击任何一个导入按钮都会弹出类似于这个的模态框：

No need to wrap the URL or ID in quotes.

在控制台中使用remix命令进行加载

两个用于加载的remix命令是：

remix.loadurl(url)
remix.loadgist(id)

remix.loadurl('https://github.com/OpenZeppelin/openzeppelin-contracts/blob/v2.5.0/contracts/math/SafeMath.sol')

remix.loadgist('5362adf2000afa4cbdd2c6d239e06bf5')

访问从主页选项卡或remix命令中加载的文件

When you load from GitHub, a folder named github is created in the root of your current workspace. To import a file from the github folder, you would use a command like this:

import "github/OpenZeppelin/openzeppelin-contracts/contracts/math/SafeMath.sol";

Notice that this import statement doesn't include the version information that was in the remix.load(url) command. So it is recommended that you use the methods described at the top of this page for importing dependencies that you are not intending to edit.

Assume the .sol file that contained the import statement above is in the contracts folder. Notice that this import statement didn't need to traverse back to the github folder with a relative path like: ../github.