以下是我的反向波兰计算器的一部分。
如果输入整数，则将其推入堆栈，如果按 = ，则查看结果。但是，我想添加另一个条件：如果用户按下 CTRL + D ，程序将退出。
我在网上看过，但似乎无法找到任何解决方案。有任何想法吗？谢谢。
Scanner mySc = new Scanner(System.in);
//If input is an integer, push onto stack.
if (mySc.hasNextInt()) {
myStack.push(mySc.nextInt());
}
//Else if the input is an operator or an undefined input.
else if (mySc.hasNext()) {
//Convert input into a string.
String input = mySc.nextLine();
//Read in the char at the start of the string to operator.
char operator = input.charAt(0);
if (operator == '=') {
//Display result if the user has entered =.
}
**else if ("CTRL-D entered") {
System.exit(0);
}**
答案 0 :(得分：1)
试试这个：
var someLargeNumber = 5000000000;
onmessage = function(e) {
console.log('Message received from main script');
for(var i = 0; i < someLargeNumber; i++) {}
console.log('Posting message back to main script');
postMessage('done');
}
在这种情况下，按 CTRL + D 时循环将停止，因为 CTRL + D 向<head>
<script>
var myWorker = new Worker("worker.js");
function hello() {
document.getElementById('hi').innerHTML = "hi";
myWorker.postMessage('test');
console.log('Message posted to worker');
}
myWorker.onmessage = function(e) {
result.textContent = e.data;
console.log('Worker thread is complete');
}
</script>
public static void main(String[] args) {
try {
byte[] b = new byte[1024];
for (int r; (r = System.in.read(b)) != -1;) {
String buffer = new String(b, 0, r);
System.out.println("read: " + buffer);
}
} catch (Exception e) {
e.printStackTrace();
}
}
EOF发送System.in信号。在* nix系统上就是这种情况，对于Windows系统，使用 CTRL + Z 组合键发送InputStream信号
答案 1 :(得分：0)
我假设您在谈论控制台应用程序？
在unix系统上，按 Ctrl + D 关闭应用程序的stdin。
这将导致@FXML
private void mouseHoverInfo() {
ImageViewInternalMouseHoverTracker ivimht = new ImageViewInternalMouseHoverTracker(this.imageView);
String xPos = ivimht.getX();
String yPos = ivimht.getY();
String colorRed = ivimht.getR();
String colorBlue = ivimht.getG();
String colorGreen = ivimht.getB();
String hexColor = ivimht.getHex();
String pixelInfo = "X: " + xPos + " Y: " + yPos + " | "
+ "r: " + colorRed + " g: " + colorGreen +
" b: " + colorBlue + " | " + hexColor;
mainApp.getPixelInfo().setInfoString(pixelInfo);
}
下方的输入流关闭，这将导致SELECT A.id, A.name, t.*
FROM A
LEFT JOIN (
SELECT B.*
FROM B
LEFT JOIN B b_
ON b.AID = b_.AID
AND b.buy_date<b_.buy_date
WHERE b_.id IS NULL
) t
ON A.id = t.AID
WHERE A.name LIKE '%to%'
返回false。
在Windows上，用户需要按 Ctrl + Z 输入才能获得相同的效果。
如果输入流尚未关闭，则Scanner会阻止，直到它返回mySc.hasNext()。
因此，您需要将程序包装在mySc.hasNext()循环中，例如
true答案 2 :(得分：0)
尝试使用此代码。它实际上对我有用
// press ctrl+Z(windows) and ctrl+D(mac, linux) for input termination
StringBuilder out = new StringBuilder();
String text = null;
Scanner scanner = new Scanner( System.in );
while( scanner.hasNextLine() )
{
text = new String( scanner.nextLine() );
out.append( text );
}
scanner.close();
System.out.println( out );
System.out.println( "program terminated" );