將檔案下的“0001.jpg,0002.jpg,0003.jpg….”改為“0.jpg,1.jpg,2.jpg…”格式
採用同步的方式遍歷，一般用非同步方式。

var fs = require('fs');
var fileDirectory = "d:\\coorsjson";
var newfileDirectory = "d:\\newname";
if (fs.existsSync(fileDirectory)) {
    var files = fs.readdirSync(fileDirectory);

    for (var i = 0; i < files.length; i++) {

        var
 
 filePath = fileDirectory + "/" + files[i];
        var name = parseInt(files[i].slice(0, -4), 10) - 1;
        console.log(name);
        var fileName = name.toString() + ".jpg";
        var newFilePath = newfileDirectory + "/" + fileName;

        fs.rename(filePath, newFilePath, function(err) {
            if
 
 (err) throw err;

            console.log(fileName + ' ok~');
        });
    }
} else {
    console.log(fileDirectory + "  Not Found!");
}