Can'；当循环中断时，不能让Java执行
我的钱包程序有一个简单但令人不快的问题，在向钱包中添加钱时，一切似乎都正常工作，但在输入“-1”作为我的钱选项时，我似乎无法打破do-while循环Can'；当循环中断时，不能让Java执行,java,loops,do-while,Java,Loops,Do While,我的钱包程序有一个简单但令人不快的问题，在向钱包中添加钱时，一切似乎都正常工作，但在输入“-1”作为我的钱选项时，我似乎无法打破do-while循环 private static void AddItemToWallet()throws IOException{ boolean valid=true; String input; int moneyChoice; char addToWallet; do{ out.println("\n\n=========================
private static void AddItemToWallet()throws IOException{
boolean valid=true;
String input;
int moneyChoice;
char addToWallet;
do{
out.println("\n\n======================================================");
do{
out.println("Please enter choice to add (integer) --->");
//display money choices
System.out.println("Avaliable moneys to add:\n");
for (Money money : Money.values()) {
System.out.print(money.ordinal()+1 + " --- ");
System.out.print(money + ": ");
System.out.println(money.GetDenom());
}
//scanner=new Scanner(in);
moneyChoice=scanner.nextInt();
if (moneyChoice > 11 || moneyChoice <= -2 || moneyChoice == 0) {
out.println("Your choice is not valid.");
}
}while(moneyChoice > 11 || moneyChoice <= -2 || moneyChoice ==0);
out.println(moneyChoice);
do{
try{
valid=false;
scanner=new Scanner(in);
//confirm choice
out.println("Add item to wallet? (y/n)");
input=scanner.nextLine();
addToWallet=input.charAt(0);
if (Character.toLowerCase(addToWallet)=='n'){
out.println("Selection " + moneyChoice + " was not added to wallet.");
valid=true;
}else if (Character.toLowerCase(addToWallet)=='y'){
out.println("Selection " + moneyChoice + " was added to wallet.");
valid=true;
Money money = Money.PENNY;
if(moneyChoice ==1){
money = Money.PENNY;
wallet.add(money.GetDenom());
}
if(moneyChoice ==2){
money = Money.NICKLE;
wallet.add(money.GetDenom());
}
if(moneyChoice ==3){
money = Money.DIME;
wallet.add(money.GetDenom());
}
if(moneyChoice ==4){
money = Money.QUARTER;
wallet.add(money.GetDenom());
}
if(moneyChoice ==5){
money = Money.HALFDOLLAR;
wallet.add(money.GetDenom());
}
if(moneyChoice ==6){
money = Money.ONE;
wallet.add(money.GetDenom());
}
if(moneyChoice ==7){
money = Money.FIVE;
wallet.add(money.GetDenom());
}
if(moneyChoice ==8){
money = Money.TEN;
wallet.add(money.GetDenom());
}
if(moneyChoice ==9){
money = Money.TWENTY;
wallet.add(money.GetDenom());
}
if(moneyChoice ==10){
money = Money.FIFTY;
wallet.add(money.GetDenom());
}
if(moneyChoice ==11){
money = Money.HUNDRED;
wallet.add(money.GetDenom());
}
System.out.println(money);
//Using a Switch and set ENUM
Money foundMoney = money;
switch (foundMoney) {
case PENNY:
money = Money.PENNY;
System.out.println("Pennies are useless");
break;
case NICKLE:
System.out.println("Why did the fan go to the concert? To get their Nickle back!!! Man are they horrible.");
break;
case DIME:
System.out.println("How come Dimes are the smallest coin? So strange.");
break;
case QUARTER:
System.out.println("Tom Brady, best Quarterback eva!!!!");
break;
case HALFDOLLAR:
System.out.println("Half Dollar coin. Have you seen one???");
break;
case ONE:
System.out.println("One is the lonliest number.");
break;
case FIVE:
System.out.println("Five Buck Lunch, here I come!!!");
break;
case TEN:
System.out.println("Ten is what grandma gave you for graduation.");
break;
case TWENTY:
System.out.println("Twenty Bucks. 2 0... awesome.");
break;
case FIFTY:
System.out.println("Fitty Sploondocks.");
break;
case HUNDRED:
System.out.println("I did it for the Benjamins. Get rich or die trying.");
break;
}
}
}catch(Exception ex){
}
if (!valid){
out.println("That is not a valid answer");
}
}while(!valid);
}while(moneyChoice!= -1);
private static void AddItemToWallet（）引发IOException{
布尔有效=真；
字符串输入；
国际货币选择；
char addToWallet；
做{
out.println（“\n\n===========================================================================================”）；
做{
out.println（“请输入要添加的选项（整数）-->”；
//显示货币选择
System.out.println（“要添加的可用金额：\n”）；
for（Money:Money.values（））{
System.out.print（money.ordinal（）+1+“-”）；
系统输出打印（货币+“：”）；
System.out.println（money.GetDenom（））；
}
//扫描仪=新扫描仪（英寸）；
moneyChoice=scanner.nextInt（）；
如果（moneyChoice>11 | | moneyChoice 11 | | moneyChoice您的程序基本上可以简化为以下内容
do {
// read moneyChoice
do {
// Perform logic
} while ( ! valid );
} while ( moneyChoice != -1 );
请注意，在阅读moneyChoice
之后，您总是进入执行逻辑的do
。没有任何东西可以检查您输入的moneyChoice
是否为-1
。因此，逻辑仍然会执行，只有在您点击while（moneyChoice！=-1）
时，它才会停止
您应该添加一个if
，这样只有在读取的moneyChoice
不是-1时才会执行逻辑
do {
// read moneyChoice
if ( moneyChoice != -1 ) {
do {
// Perform logic
} while ( ! valid );
}
} while ( moneyChoice != -1 );
在逐行调试的过程中，您了解到…？您应该将其分解为更小的方法。这是不必要的困难。您还应该正确地缩进代码。大多数人会发现4个空格更适合java语法…并删除重复的代码。您只需要一个wallet.add（money.GetDenom（））；
--在一系列的if
语句之后，不要在if
语句的每个“then”块中。虽然与您的问题没有直接关系，但是养成从不写空catch
块的习惯是个好主意