Question

当我按住键盘上的ENTER键时，readline模块将向我的可写流输出空行（在本例中为process.stdout）。

但是，由于我不希望空行使控制台混乱，所以我想以某种方式阻止它输出。

我可以使用某些方法来过滤流中的空行吗？也许使用某种转换流？

const readline = require("readline");

const rl = readline.createInterface({
  input: process.stdin,
  output: process.stdout,
  removeHistoryDuplicates: true
});

rl.on("line", (line) => {
  if(line.trim().length === 0) {
    // don't output anything, but it is already too late because it is already written to stream :'-(
  }
  rl.prompt();
})

Answer 1

使用此

   readline.cursorTo(process.stdout, 0,0);

输入将被自动忽略并返回到开头

https://nodejs.org/api/readline.html#readline_readline_clearline_stream_dir

const readline = require("readline");

const rl = readline.createInterface({
  input: process.stdin,
  output: process.stdout,
  removeHistoryDuplicates: true
});


const enterPressed=(line)=>{
    return line.replace(/[^a-zA-Z]/g, "").trim().length === 0
}

rl.on("line", (line) => {

  if(enterPressed(line)) {
     readline.cursorTo(process.stdout, 0,0);
  }
  rl.prompt();
})

防止在节点readline中输出空行

1 个答案: