使用 Node.js 写入文件
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Wiriting a file
The easiest way to write to files in Node.js is to use the fs.writeFile() API.
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Writing a file synchronously
Alternatively, you can use the synchronous version fs.writeFileSync():
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You can also use the promise-based fsPromises.writeFile() method offered by the fs/promises module:
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By default, this API will replace the contents of the file if it does already exist.
You can modify the default by specifying a flag:
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The flags you'll likely use are
| Flag | Description | File gets created if it doesn't exist |
|---|---|---|
r+ | This flag opens the file for reading and writing | ❌ |
w+ | This flag opens the file for reading and writing and it also positions the stream at the beginning of the file | ✅ |
a | This flag opens the file for writing and it also positions the stream at the end of the file | ✅ |
a+ | This flag opens the file for reading and writing and it also positions the stream at the end of the file | ✅ |
- You can find more information about the flags in the fs documentation.
Appending content to a file
Appending to files is handy when you don't want to overwrite a filewith new content, but rather add to it.
Examples
A handy method to append content to the end of a file is fs.appendFile() (and its fs.appendFileSync() counterpart):
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Example with Promises
Here is a fsPromises.appendFile() example:
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