node.js学习第一篇

Posted 2022-01-31 passerma

这篇从一个基本的读取本地文件案例，大概介绍了node.js的写法，代码如下

 1 var fs = require(‘fs‘);
 2 var stats = [];
 3 fs.readdir(process.cwd(), function(err, files)
 4     console.log(files);
 5     console.log(‘ ‘);
 6     if(!files.length)
 7         return console.log(‘  \033[31m No file to show!\033[39m\n‘);
 8     
 9     console.log(‘  Select which file or directory you want to see\n‘);
10     function file(i) 
11         var filename = files[i];
12         fs.stat(__dirname + ‘/‘ +filename, function (err, stat) 
13             stats[i] = stat;
14             if(stat.isDirectory())
15                 console.log(‘  ‘+i+‘  \033[36m‘ + filename + ‘/\033[39m‘);
16              else 
17                 console.log(‘  ‘+i+‘  \033[90m‘ + filename + ‘\033[39m‘);
18             
19             i++;
20             if(i == files.length)
21                 console.log(‘ ‘);
22                 process.stdout.write(‘  \033[33mEnter your choice: \033[39m‘);
23                 process.stdin.resume();
24                 process.stdin.setEncoding(‘utf8‘);
25                 process.stdin.on(‘data‘, function (data) 
26                     var filename = files[Number(data)];
27                     if(!files[Number(data)])
28                         process.stdout.write(‘  \033[33mEnter your choice: \033[39m‘);
29                      else 
30                         process.stdin.pause();
31                         if(stats[Number(data)].isDirectory())
32                             fs.readdir(__dirname + ‘/‘ +filename, function (err, files) 
33                                 console.log(‘ ‘);
34                                 console.log(‘  ( ‘+files.length + ‘files )‘);
35                                 files.forEach(function (file) 
36                                     console.log(‘  -  ‘ + file);
37                                 );
38                                 console.log(‘ ‘)
39                             )
40                          else 
41                             fs.readFile(__dirname+‘/‘+filename, ‘utf8‘, function (err, data) 
42                                 console.log(‘ ‘);
43                                 console.log(‘\033[90m‘+ data.replace(/(.*)/g, ‘  $1‘)+‘\033[39m‘);
44                             )
45                         
46                     
47                 )
48              else 
49                 file(i);
50             
51         )
52     
53     file(0);
54 );