Node.js fs.Dirent.isCharacterDevice() 方法
fs.Dirent.isCharacterDevice()方法是文件系统模块中fs.Dirent类的内置应用程序编程接口,用于检查特定的 dirent 是否描述了字符设备。
句法:
const dirent.isCharacterDevice()
参数:此方法不接受任何参数。
返回值:如果特定的dirent描述了字符设备,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.isCharacterDevice()方法的使用:
示例 1:
文件名:index.js
Javascript
// Node program to demonstrate the
// dirent.isCharacterDevice() method
const fs = require('fs');
// Initiating async function
async function stop(path) {
// Creating and initiating directory's
// underlying resource handle
const dir = await fs.promises.opendir(path);
// Synchronously reading the directory's
// underlying resource handle using
// readSync() method
for (var i = 0; i <= 3; i++) {
// Checking if the particular dirent
// is Character device or not by using
// isCharacterDevice() method
const value = (dir.readSync())
.isCharacterDevice();
// Display the result
console.log(dir.readSync());
console.log(value);
}
}
// Catching error
stop('./').catch(console.error);
Javascript
// Node program to demonstrate the
// dirent.isCharacterDevice() method
const fs = require('fs');
// Initiating async function
async function stop(path) {
// Creating and initiating directory's
// underlying resource handle
const dir = await fs.promises
.opendir(new URL('file:///F:/'));
// Synchronously reading the directory's
// underlying resource handle using
// readSync() method
for (var i = 0; i <= 3; i++) {
// Checking if the particular dirent
// is Character device or not by
// using isCharacterDevice() method
const value = (dir.readSync())
.isCharacterDevice();
// Display the result
console.log(dir.readSync());
console.log(value);
}
}
// 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 }
false
Dirent { name: 'certificate1.cer', [Symbol(type)]: 1 }
false
Dirent { name: 'filename.txt', [Symbol(type)]: 1 }
false
Dirent { name: 'GFG.java', [Symbol(type)]: 1 }
false
示例 2:
文件名:index.js
Javascript
// Node program to demonstrate the
// dirent.isCharacterDevice() method
const fs = require('fs');
// Initiating async function
async function stop(path) {
// Creating and initiating directory's
// underlying resource handle
const dir = await fs.promises
.opendir(new URL('file:///F:/'));
// Synchronously reading the directory's
// underlying resource handle using
// readSync() method
for (var i = 0; i <= 3; i++) {
// Checking if the particular dirent
// is Character device or not by
// using isCharacterDevice() method
const value = (dir.readSync())
.isCharacterDevice();
// Display the result
console.log(dir.readSync());
console.log(value);
}
}
// 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: 'adonis_auth_api', [Symbol(type)]: 2 }
false
Dirent { name: 'Android Template', [Symbol(type)]: 2 }
false
Dirent { name: 'Calander', [Symbol(type)]: 2 }
false
Dirent { name: 'first-app', [Symbol(type)]: 2 }
false
参考: https://nodejs.org/dist/latest-v12.x/docs/api/fs.html#fs_dirent_ischaracterdevice