Node.js fs.Dirent.isFile() 方法

fs.Dirent.isFile()方法是文件系统模块中fs.Dirent类的内置应用程序编程接口，用于检查特定 dirent 是否描述了文件。

句法：

const dirent.isFile()

参数：此方法不接受任何参数。
返回值：如果特定的dirent描述了一个文件，则此方法返回true，否则返回false。
下面的程序说明了 node.js 中fs.dirent.isFile()方法的使用：
示例 1：
文件名：index.js

javascript

// Node.js program to demonstrate the
// dirent.isFile() method
const fs = require('fs');
 
// Initiating async function
async function stop(path) {
 
  // Creating and initiating File's
  // underlying resource handle
  const dir = await fs.promises.opendir(path);
   
  // Synchronously reading the File's
  // underlying resource handle
  // using readSync() method
  for(var i = 0; i <= 3; i ++ ) {
 
    // Checking if the particular dirent is
    // File  or not by using isFile() method
    const value = (dir.readSync()).isFile();
 
    // Display the result
    console.log(dir.readSync());
    console.log(value);
  }
}
 
// Catching error
stop('./').catch(console.error);

javascript

// Node.js program to demonstrate the
// dirent.isFile() method
const fs = require('fs');
   
// Initiating async function
async function stop(path) {
  
  let dir = null;
   
  try {
 
    // Creating and initiating directory's
    // underlying resource handle
    dir = await fs.promises.opendir(
        new URL('file:///F:/java/'));
 
    // Synchronously reading the File's
    // underlying resource handle
    // using readSync() method
    for(var i = 0; i <= 3; i ++ ) {
 
      // Checking if the particular dirent
      // is File or not by using isFile() method
      const value = (dir.readSync()).isFile();
   
      // Display the result
     console.log(dir.readSync());
     console.log(value);
    }
  } finally {
  
    if (dir) {
 
      // Display the result
      console.log("dir is closed successfully");
 
      // Synchronously closeSyncing the
      // directory's underlying resource
      // handle
      const promise = dir.closeSync();
    }
  }
}
   
// catching error
stop('./').catch(console.error);

使用以下命令运行index.js文件：

node index.js

输出：

Dirent { name: 'cert.cer', [Symbol(type)]: 1 }
true
Dirent { name: 'certificate1.cer', [Symbol(type)]: 1 }
true
Dirent { name: 'filename.txt', [Symbol(type)]: 1 }
false
Dirent { name: 'GFG.java', [Symbol(type)]: 1 }
true

示例 2：
文件名：index.js

javascript

// Node.js program to demonstrate the
// dirent.isFile() method
const fs = require('fs');
   
// Initiating async function
async function stop(path) {
  
  let dir = null;
   
  try {
 
    // Creating and initiating directory's
    // underlying resource handle
    dir = await fs.promises.opendir(
        new URL('file:///F:/java/'));
 
    // Synchronously reading the File's
    // underlying resource handle
    // using readSync() method
    for(var i = 0; i <= 3; i ++ ) {
 
      // Checking if the particular dirent
      // is File or not by using isFile() method
      const value = (dir.readSync()).isFile();
   
      // Display the result
     console.log(dir.readSync());
     console.log(value);
    }
  } finally {
  
    if (dir) {
 
      // Display the result
      console.log("dir is closed successfully");
 
      // Synchronously closeSyncing the
      // directory's underlying resource
      // handle
      const promise = dir.closeSync();
    }
  }
}
   
// catching error
stop('./').catch(console.error);

使用以下命令运行index.js文件：

node index.js

输出：

Dirent { name: 'cert.cer', [Symbol(type)]: 1 }
true
Dirent { name: 'certificate1.cer', [Symbol(type)]: 1 }
true
Dirent { name: 'features', [Symbol(type)]: 2 }
true
Dirent { name: 'GFG.class', [Symbol(type)]: 1 }
true
dir is closed successfully

参考： https://nodejs.org/dist/latest-v12.x/docs/api/fs.html#fs_dirent_isfile