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我写了一个代码来创建.csv文件，并希望读取它并使用node存储在数据库中。下面是源代码（我跟随YouTube视频）： const fs = require(fs);
(async () => {
const writeStream = fs.createWriteStream('out.csv');
for(let i=0; i< 1e8; i++){
const over= writeStream.write(`${i},1\n`);
if(!over){
await new Promise((resolve) => writeStream.once('drain', resolve))
}
}
writeStream.end();
})然而我得到错误;#app crashed，Cannot access 'fs' before initialization.有人能帮忙吗？我也不知道如何将数据保存到数据库中。我也写了readStream代码： const fs = require(fs);
(async () => {
const readStream = fs.createReadStream('out.csv');
let sum=0;
let unprocessed='';
readStream.on('data', (chunk) => {
let chunkString = unprocessed+ chunk.toString();
unprocessed='';
let startIndex=0;
for(let ch=startIndex; ch< chunkString.length; ch++){
if(chunkString[ch] === '\n'){
const line= chunkString.slice(startIndex, ch),
idx= line.indexOf(','),
cost= line.slice(idx+1);
sum += parseFloat(cost);
startIndex= ch+1;
}
}
})
if(chunkString[chunkString.length-1]!=='\n'){
unprocessed= chunkString.slice(startIndex);
}
});
readStream.on('end', ()=> {
console.log(`sum: ${sum}`)
})
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