Several implementation methods for JavaScript to access local folders

JavaScript in a browser environment (usually refers to front-end JavaScript) cannot directly access the user's local files or folders due to security restrictions. This is to prevent malicious scripts from accessing and stealing sensitive data from users.

However, there are several ways to indirectly let the user select and access local files:

use<input type="file">element：

This is the standard way for front-end JavaScript to access files selected by users. Users can select one or more files through the file selection dialog box, and then you can use JavaScriptFile APIto read the contents of these files.

<input type="file" >

<script>
  const inputElement = ('myFileInput');
  ('change', handleFiles, false);

  function handleFiles() {
    const fileList = ;
    const reader = new FileReader();

     = function(e) {
      (); // Print the file content    };

    // Read the first file    (fileList[0]);
  }
</script>

Using the drag and drop API：

Although not commonly used, you can use the drag and drop API to let users drag and drop files to specific areas of a web page and then read them.

Using Web APIs (such as File System Access API)：

In newer browser versions, there are experimental web APIs that allow more complex file access, such as the File System Access API. Note, however, that these APIs may not be widely supported in all browsers and may require explicit permissions from users.

File access in：

If you work in the environment (i.e. server-side JavaScript), you can use the built-in onefsmodule to access the local file system. It is not subject to security restrictions in the browser, so files can be read and written freely.

const fs = require('fs');

('/path/to/file', 'utf8', (err, data) => {
  if (err) throw err;
  (data);
});

Using Electron and other frameworks：

If you are developing a desktop application and want to access local files using JavaScript, you can use frameworks like Electron. Electron allows you to build cross-platform desktop applications using Web technologies (HTML, CSS, JavaScript) and have full local file access.

Through user interaction or command line parameters：

For certain specific scenarios (such as scripts running through the command line), you can specify the path to the local file or folder to access through command line parameters or user input.

In short, front-end JavaScript cannot directly access the user's local files or folders, but indirect access can be achieved through user interaction and specific Web APIs. In environments like Electron, you can have more freedom to access your local file system.

This is the end of this article about several implementation methods for JavaScript to access local folders. For more related contents of JavaScript to access local folders, please search for my previous articles or continue browsing the related articles below. I hope everyone will support me in the future!