作为javascript开发,node如何读取json配置文件?


在Node.js中,你可以使用内置的fs模块来读取JSON配置文件。以下是一个简单的例子: ```javascript const fs = require('fs'); fs.readFile('config.json', 'utf8', (err, data) => { if (err) throw err; const config = JSON.parse(data); console.log(config); }); ``` 在这个例子中,我们首先导入了fs模块,然后使用fs.readFile方法来读取config.json文件。这个方法接受三个参数:文件路径,编码类型(在这个例子中是'utf8'),以及一个回调函数。回调函数接受两个参数:错误(如果有的话)和文件内容。 如果文件读取成功,我们使用JSON.parse方法将文件内容解析为一个JavaScript对象。然后,我们可以像操作任何其他JavaScript对象一样操作这个配置对象。 注意,这个例子假设config.json文件是一个有效的JSON文件。如果文件内容不是有效的JSON,JSON.parse方法会抛出一个错误。你可能需要在调用JSON.parse方法之前添加一些错误检查代码。 [2023-11-09 00:56:05 | AI写代码神器 | 221点数解答]
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