NPM可用于在项目中安装和管理依赖项的版本。

我在React版本和npm版本上也遇到了同样的问题:

NPM错误发现类型/react@16.14.20

因此，它可能是需要根据您的包安装的包版本。json文件。

它会在npm 7版本中给出错误，并且无法安装Node.js模块。

如果你将npm版本降级到6，这些问题将变成警告，问题将得到解决。

试着证明这个命令:npm install -g npm@6 检查版本是否已经安装:npm——version 删除并安装node_modules包: a)删除rm -rf node_modules b)安装:npm i

只需做两个简单的步骤:

首先，在终端中执行这个命令。

npm config set legacy-peer-deps true

其次，清除缓存:

npm cache clean --force

最后，执行你的命令。这肯定有用。

Use

npm install --legacy-peer-deps

这对我很管用。

在我的例子中，我遇到了@babel/core依赖的问题，但我不想使用——force，因为我不确定后果，所以我去https://www.npmjs.com/，寻找包并用最新的包替换了我的旧版本。这就成功了。

免责声明:这假设你使用的是npm v7

注意:如果你遵循兄弟注释的指示，它将创建一个用户范围的配置，不会在队友/机器/构建机器人之间保持同步。

基于项目的遗留对等依赖

您可能希望将遗留同行deps与您的项目绑定在一起，以便它在机器/开发人员之间扩散，而不会污染您的其他项目。

npm config set legacy-peer-deps true --location project

这将创建一个本地文件在.npmrc，你可以提交到你的存储库:

legacy-peer-deps=true

然后，你就可以跑了:

npm install

然后提交更新后的锁文件。

记住，位置，位置，位置:

per-project configuration (/path/to/my/project/.npmrc, see more): npm config set legacy-peer-deps true --location project per-user configuration (defaults to $HOME/.npmrc, see more) npm config set legacy-peer-deps true --location user or, as the default location is user anyway: npm config set legacy-peer-deps true global configuration (defalts to $PREFIX/etc/npmrc, see more) npm config set legacy-peer-deps true --location global or, as --global infers --location global npm config set legacy-peer-deps true --global

对于某些项目，修复依赖关系可能不是简单的

在我的案例中，我们有一个遗留版本的关键依赖项想要引入webpack v3(!) -但这是该项目的构建依赖项。

短期内最好的解决方案是使用遗留peer-deps作为保留。

如果你在紧要关头，你也可以考虑对依赖项进行分叉，并相应地调整它的对等依赖项——它们将你的项目指向分叉。

首先要了解问题。以下是我的错误:

npm ERR! ERESOLVE unable to resolve dependency tree
npm ERR!
npm ERR! While resolving: project-admin@11.0.0
npm ERR! Found: @angular/common@11.0.3
npm ERR! node_modules/@angular/common
npm ERR!   @angular/common@"11.0.3" from the root project
npm ERR!
npm ERR! Could not resolve dependency:
npm ERR! peer @angular/common@"^9.1.0 || ^10.0.0" from @agm/core@3.0.0-beta.0
npm ERR! node_modules/@agm/core
npm ERR!   @agm/core@"3.0.0-beta.0" from the root project

首先，你应该从下到上读这道题。这里@agm/core@3.0.0-beta.0需要通用的angular 9.1.0或10.0.0。最上面的消息说，角的公共发现实际上是11.0.3。

(如果你想更好地理解依赖关系，这里有一个非常简单的网站:如何npm3工作)

dependencies — these are the essential dependencies that you rely on and call in your project’s code
devDependencies — these are your development dependencies, for example, a prettier library for formatting code
peerDependencies — if you set a peer dependency in your package.json, you are telling the person who installs your package that they need that dependency with the specified version
optionalDependencies — these dependencies are optional and failing to install them will not break the installation process
bundledDependencies — it’s an array of packages that will come bundled with your package. This is useful when some 3rd party library is not on NPM, or you want to include some of your projects as modules

So what should be the solution then? The problem is about peer dependencies. The solution is to downgrade angular common or the solution is to use legacy dependencies logic for installing packages using --legacy-peer-deps. So --legacy-peer-deps does not try to install the peerDependencies automatically. Is this going to work for you? Probably, yes. But you should add specific instructions how to do that, or to make the use of --legacy-peer-deps automatic for future installation of the project packages with this code from one of the previous answers:

npm config set legacy-peer-deps true

In my case I installed the package and I tried to run ng serve, but because --legacy-peer-deps was used, there were dependency packages which were not installed. I had to install those manually (because I did not set the configuration from the code above). At the end installing about five packages manually, all with --legacy-peer-deps, I ended to a package that could not be installed and I did not try to continue, because my project was throwing warnings like crazy and there were a lot of packages for audit too. So my decision was not to use this package and to find an alternative.

我读到的其他解决方案:

downgrade Node.js to v14. This will downgrade npm. It might not be v14, but this was the version that was most widely downgraded to. Some people use Yarn to force package installation - personally I don't understand how this works, because I haven't used Yarn. downgrading Angular and the global Angular CLI version to version that will satisfy the requirement. In my case it is angular/common, and in the question it's angular/core, but both require downgrading the whole angular right (I am not sure about this here). the package you install might have a higher version that doesn't require downgrading Angular. You might try to use the https://updatepackagejson.com/ to upgrade your packages to the latest, but this is in case your project is quite new.