node读取文本文件并处理输出

var readline = require('readline');
var fs = require('fs');
var os = require('os');

var fReadName = './Loclistcn.xml';//源文件
var fWriteName = './LocListcn1.xml';//目标文件
var fRead = fs.createReadStream(fReadName);
var fWrite = fs.createWriteStream(fWriteName);

var enableWriteIndex = true;
var enableWriteIndex1 = true;
fRead.on('end', ()=>{
    console.log('end');
    enableWriteIndex = false;
});

var index = 1;
var arr = [];
var code = ""
var country = ""

var objReadline = readline.createInterface({
    input: fRead,
    output: fWrite,
    /*terminal: true*/
});
objReadline.on('line', (line)=>{
//正则处理
    var rg1 = /(<State)(.*)(Code=")([a-zA-Z 0-9]*)(">)/
    var rg3 = /(<State)(.*)(>)/
    var rg4 = /(<CountryRegion)(.*)(Code=")([a-zA-Z 0-9]*)(">)/
    var rg2 = /(<City.*)(Code=")([a-zA-Z 0-9]*)((".*\/>)|(">))/
    var rg6 = /(<\/City.*)(>)/
    var rg5 = /( <Region .*)(Code=")([a-zA-Z 0-9]*)(".*)(\/>)/
    var str1
    if(rg1.test(line)){
        code =line.replace(rg1,RegExp.$4).trim()
    }else if(rg3.test(line)){
        code = ""
    }
    if(rg4.test(line)){
        country =line.replace(rg4,RegExp.$4).trim()
    }

    if(rg2.test(line)){
        str1 =line.replace(rg2,RegExp.$1 + ' cityCode="'+ (code ? (code+'-') : code)+ RegExp.$3+ '"' +
            ' countryCode="'+ country + '" ' +RegExp.$2 + RegExp.$3 +(RegExp.$4 ==='">' ?  ' "/>' : RegExp.$4 ))
    }else{
        str1 = line
    }
    if(!rg5.test(line) && !rg6.test(line)){
        var tmp =str1 + '\n';
        // console.log(tmp)
        str1 && fWrite.write(tmp);
    }
    index ++
});
objReadline.on('close', ()=>{
    console.log('readline close...');
});