我试图在我的Java类的最后一分钟完成此操作，当我在询问用户信息是否正确后运行程序时，无论如何都会循环回到第一个问题。这是代码：
import java.util.Scanner;
public class InterestCalculator {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
String userResponse = null;
do {
int quartersDisplayed = -1;
double startingBalance = -1,
interestRate = -1;
do {
System.out.println("Enter the numbers of quarters you wish to display that is greater than zero and less or equal to 10: ");
userResponse = input.next();
try{
quartersDisplayed = Integer.parseInt(userResponse);
} catch(NumberFormatException e) {
}
if(quartersDisplayed <= 0 || quartersDisplayed > 10) {
System.out.println("Sorry, that value is not valid.");
} else {
break;
}
} while(true);
do {
System.out.println("Enter the starting balance (must be greater than zero): ");
userResponse = input.next();
try {
startingBalance = Double.parseDouble(userResponse);
} catch(NumberFormatException e) {
}
if(startingBalance <= 0) {
System.out.println("Sorry, that value is not valid.");
} else {
break;
}
} while(true);
do {
System.out.println("Enter the interest rate (greater than zero less than twenty percent): ");
userResponse = input.next();
try {
interestRate = Double.parseDouble(userResponse);
} catch(NumberFormatException e) {
}
if(interestRate <= 0 || interestRate > 20){
System.out.println("Sorry, that value is not valid.");
} else {
break;
}
} while(true);
System.out.println("You have entered the following amount of quarters: "
+ quartersDisplayed);
System.out.println("You also entered the starting balance of: " + startingBalance);
System.out.println("Finally, you entered the following of interest rate: "
+ interestRate);
System.out.println("If this information is not correct, please exit the program and enter the correct information.");
double quarterlyEndingBalance = startingBalance + (startingBalance * interestRate / 100 * .25);
System.out.println("Your ending balance for your quarters is "
+ quarterlyEndingBalance);
System.out.println("Do you want to continue?");
userResponse = input.next();
if("y".equalsIgnoreCase(userResponse) || "yes".equalsIgnoreCase(userResponse))
continue;
else
break;
} while(true);
}
}
我正在寻找的样本输出：
Enter number of quarters from 1 to 10
5
Enter the beginning principal balance greater than zero
4500
Enter the interest rate percentage without the percent sign, greater than 0 percent and less than/equal to 20%
3.5
You entered a principal balance of $4500.0 for 5 quarters at 3.5% interest.
Is this correct? (y/n)
y
Quarter Beginning Interest Ending
Number Balance Earned Balance
1 4500.00 39.38 4539.38
答案 0 :(得分：0)
如果输入错误，也许你要做的就是重启循环。在这种情况下，您只需切换continue和break即可。
continue语句使循环立即开始下一次迭代。您应该通过空语句;删除它，或者否定if - 条件，删除else并在break上设置true。此外，您的代码不做任何其他事情，然后获取输入并询问它是否正确。因为它是在do...while(true)循环内写的，所以这个循环永远不会结束。因此，要么删除该循环，要么添加一个选项以中止该过程。
答案 1 :(得分：0)
Your code should look something like the one below...
**Look out to the bottom, where the user is informed of the values entered and check for the changes made**. This is quite simple...
import java.util.Scanner;
public class correctstack{
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
String userResponse = null;
do {
int quartersDisplayed = -1;
double startingBalance = -1,
interestRate = -1;
do {
System.out.println("Enter the numbers of quarters you wish to display that is greater than zero and less or equal to 10: ");
userResponse = input.next();
try{
quartersDisplayed = Integer.parseInt(userResponse);
} catch(NumberFormatException e) {
}
if(quartersDisplayed <= 0 || quartersDisplayed > 10) {
System.out.println("Sorry, that value is not valid.");
} else {
break;
}
} while(true);
do {
System.out.println("Enter the starting balance (must be greater than zero): ");
userResponse = input.next();
try {
startingBalance = Double.parseDouble(userResponse);
} catch(NumberFormatException e) {
}
if(startingBalance <= 0) {
System.out.println("Sorry, that value is not valid.");
} else {
break;
}
} while(true);
do {
System.out.println("Enter the interest rate (greater than zero less than twenty percent): ");
userResponse = input.next();
try {
interestRate = Double.parseDouble(userResponse);
} catch(NumberFormatException e) {
}
if(interestRate <= 0 || interestRate > 20){
System.out.println("Sorry, that value is not valid.");
} else {
break;
}
} while(true);
System.out.println("You have entered the following amount of quarters: "+ quartersDisplayed);
System.out.println("You also entered the starting balance of: " + startingBalance);
System.out.println("Finally, you entered the following of interest rate: "+ interestRate);
System.out.println("If this information is not correct, please exit the program and enter the correct information.");
//Here, you give the user the opportunity to continue or re-enter the values. So you go like...
System.out.println("Is this info correct?");
String user_input = input.next();
if("y".equalsIgnoreCase(user_input) || "yes".equalsIgnoreCase(user_input)){
double quarterlyEndingBalance = startingBalance + (startingBalance * interestRate / 100 * .25);
System.out.println("Your ending balance for your quarters is "+ quarterlyEndingBalance);
System.out.println("\n\nDo you want to continue?");
userResponse = input.next();
if("y".equalsIgnoreCase(userResponse) || "yes".equalsIgnoreCase(userResponse))
continue;
else
break;
}
else
continue;
} while(true);
}
}