fs.Dirent.isFile()方法是File System模塊內fs.Dirent類的內置應用程序編程接口,用於檢查特定Dirent是否描述了File。
用法:
const dirent.isFile()
參數:此方法不接受任何參數。
返回值:如果特定區別描述了File,則此方法返回true;否則返回false。
以下程序說明了在node.js中使用fs.dirent.isFile()方法:
範例1:
文件名:index.js
// Node.js program to demonstrate the  
// dirent.isFile() method 
const fs = require('fs'); 
  
// Initiating asyn 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() mehtod 
  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);使用以下命令運行index.js文件:
node index.js
輸出:
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
範例2:
文件名:index.js
// Node.js program to demonstrate the  
// dirent.isFile() method 
const fs = require('fs'); 
    
// Initiating asyn 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);使用以下命令運行index.js文件:
node index.js
輸出:
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
參考: https://nodejs.org/dist/latest-v12.x/docs/api/fs.html#fs_dirent_isfile
相關用法
- Node.js console.timeLog()用法及代碼示例
 - Node.js GM resize()用法及代碼示例
 - Node.js GM gamma()用法及代碼示例
 - Node.js GM spread()用法及代碼示例
 - Node.js GM transparent()用法及代碼示例
 - Node.js GM write()用法及代碼示例
 - Node.js GM negative()用法及代碼示例
 - Node.js GM median()用法及代碼示例
 - Node.js GM shave()用法及代碼示例
 - Node.js GM emboss()用法及代碼示例
 - Node.js GM despeckle()用法及代碼示例
 - Node.js GM gaussian()用法及代碼示例
 - Node.js GM magnify()用法及代碼示例
 - Node.js GM minify()用法及代碼示例
 
注:本文由純淨天空篩選整理自RohitPrasad3大神的英文原創作品 Node.js fs.Dirent.isFile() Method。非經特殊聲明,原始代碼版權歸原作者所有,本譯文未經允許或授權,請勿轉載或複製。
