Java 如何使用扫描仪获取布尔用户输入？
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How to get boolean user input using scanner?
提问by tash517
So i have to ask the user whether they are above 18 and they have to answer with a true or false. And keep looping until they enter the right input
所以我必须问用户他们是否超过 18 岁，他们必须回答真假。并继续循环直到他们输入正确的输入
So far, i have this
到目前为止，我有这个
boolean b = false;
do {
try {
System.out.print("Are you above 18?");
Scanner n = new Scanner(System.in);
boolean bn = s.nextBoolean();
if (bn == true) {
// do stuff
} else if (bn == false) {
// do stuff
}
} catch (InputMismatchException e) {
System.out.println("Invalid input!");
}
} while (!b);
HOWEVER, it wont work as the loop keeps going and it wont read the input right and do my if statements. How do i fix this? Thanks!
但是，它不会在循环继续进行时起作用，并且不会正确读取输入并执行我的 if 语句。我该如何解决？谢谢！
采纳答案by vkg
slight tweak to your program. This works
对您的程序稍作调整。这有效
boolean b = false;
do {
try {
System.out.print("Are you above 18?");
Scanner n = new Scanner(System.in);
boolean bn = n.nextBoolean();
if (bn == true) {
System.out.println("Over 18");
} else if (bn == false) {
System.out.println("under 18");
}
} catch (InputMismatchException e) {
System.out.println("Invalid input!");
}
} while (!b);
And the output is
输出是
Are you above 18?true
Over 18
Are you above 18?false
under 18
Are you above 18?
回答by Code-Apprentice
Try changing
尝试改变
boolean bn = s.nextBoolean();
to
到
b = s.nextBoolean();
回答by Hello World
Use-
用-
scanner.nextBoolean()
扫描仪.nextBoolean()
do{
try{
System.out.print("Are you above 18?");
Scanner scanner = new Scanner(System.in);
if(scanner.nextBoolean()==true)
//do stuff
}else{
//do stuff
}
}
回答by Rajat.r2
You need to re-check your Scanner statement and Initializing statement...
您需要重新检查您的 Scanner 语句和 Initializing 语句...
Scanner n = new Scanner(System.in);
boolean bn = s.nextBoolean();
It should be
它应该是
Scanner n = new Scanner(System.in);
boolean bn = n.nextBoolean();
