node.js写入文件踩坑_throw new err_invalid_callback(callback);

function writeFile(){
	fs.writeFile("how.html","bye");
	return "write successful";
	
}

报错如下：

 throw new ERR_INVALID_CALLBACK(callback);
    ^
 
TypeError [ERR_INVALID_CALLBACK]: Callback must be a function. Received undefined
[90m    at maybeCallback (node:fs:174:3)[39m
[90m    at Object.writeFile (node:fs:2091:14)[39m
    at Object.writeFile [as /writeFile] (C:\陆哥\project_nodejs\src\file\requestHandlers.js:10:5)
    at route (C:\陆哥\project_nodejs\src\router\router.js:3:26)
    at Server.onRequest (C:\陆哥\project_nodejs\src\router\server.js:7:12)
[90m    at Server.emit (node:events:394:28)[39m
[90m    at parserOnIncoming (node:_http_server:927:12)[39m
[90m    at HTTPParser.parserOnHeadersComplete (node:_http_common:128:17)[39m {
  code: [32m'ERR_INVALID_CALLBACK'[39m

查了一下发现原来是writeFile调用还需要第三个参数callback

修改如下

fu