Node.js 生成：console.log 没有记录两次并且 process.stdin.on('data',callback) 没有执行

Question

我对下面的代码有三个问题。首先，为什么线 A 不会出现在终端的输出中。现在似乎正在记录 B 行，而 A 行没有。其次，在 4000 毫秒标记之前，我尝试在键盘上输入一些内容，并预计 C 中的代码块会结束该过程。但是，它一直在写出字符串，直到达到 4 秒。当我尝试自己运行 alwaysTalking.js 时，我的键盘中断实际上会结束程序。为什么它在这里不起作用？最后，D行在做什么？是否将 spawn 函数传递给变量 spawn？那么 var spawn 是 spawn 函数/类的对象吗？

任何帮助将不胜感激！

alwaysTalking.js：

var sayings = [
"You may delay, but time will not.",
"Tell me and I forget. Teach me and I remember. Involve me and I learn.",
"It takes many good deeds to build a good reputation, and only one bad one to lose it.",
"Early to bed and early to rise makes a man healthy, wealthy and wise.",
"By failing to prepare, you are preparing to fail.",
"An investment in knowledge pays the best interest.",
"Well done is better than well said."
];

var interval = setInterval(function() {
var i = Math.floor(Math.random() * sayings.length);
console.log(` ${sayings[i]} \n`);       //line A
}, 1000);

process.stdin.on('data', function(data) {                          //C
console.log(`STDIN Data Recieved -> ${data.toString().trim()}`);   //C
clearInterval(interval);                                           //C
process.exit();                                                    //C
});                                                                //C

spawn.js：

var spawn = require("child_process").spawn;           //line D
var cp = spawn("node", ["alwaysTalking"]);

cp.stdout.on("data", function(data) {
console.log(`STDOUT: ${data.toString()}`);   //line B
});

cp.on("close", function() {
console.log("Child Process has ended");
process.exit();
});
setTimeout(function() {
cp.stdin.write("stop");
}, 4000);

在终端上：

$node spawn
STDOUT: abcde You may delay, but time will not. 


STDOUT: abcde Tell me and I forget. Teach me and I remember. Involve me and I learn. 


STDOUT: abcde By failing to prepare, you are preparing to fail. 


STDOUT: STDIN Data Recieved -> stop

Child Process has ended

Answer 1

您没有将标准输入传递给子进程。您需要：

process.stdin.pipe(cp.stdin);