Dart中的简单命令行应用程序I / O [英] Simple command-line app I/O in Dart
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问题描述
有没有一种方法从用户取单个字符(整数)键盘输入并将它们存储到Dart命令行应用程序中的变量?我试过像:
Is there a way of taking single character (integer) keyboard inputs from the user and storing them to a variable in a Dart command-line app? I've tried something like:
Stream cmdLine = stdin
.transform(new StringDecoder())
.transform(new LineTransformer());
StreamSubscription cmdSubscription = cmdLine.listen(
(line) => (choice = line);
cmdSubscription.cancel(););
尝试将键盘输入存储到变量choice但不能让它工作。
In an attempt to store a keyboard input into the variable 'choice' and many slight variations of this code but can't get it to work.
推荐答案
目前你只能一次读取一行,
Currently you can only read a whole line at a time - i.e. once enter is pressed.
为此问题。
更新:
readLine )函数等待用户的一行输入并将其作为字符串返回。
The readLine() function waits for a line of input from a user and returns it as a string.
import 'dart:async';
import 'dart:io';
main() {
print('1 + 1 = ...');
readLine().then((line) {
print(line.trim() == '2' ? 'Yup!' : 'Nope :(');
});
}
Future<String> readLine() {
var completer = new Completer<String>();
var input = stdin
.transform(new StringDecoder())
.transform(new LineTransformer());
var subs;
subs = input.listen((line) {
completer.complete(line);
subs.cancel();
});
return completer.future;
}
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