Java 依次运行两个while循环以获取用户输入
在我的方法中,我希望用户输入,如果它首先通过,而它需要转到第二个while循环,在第二个while循环中,如果条件失败,它需要重新运行循环,而不是重新运行自己,第一个while正在执行Java 依次运行两个while循环以获取用户输入,java,while-loop,do-while,Java,While Loop,Do While,在我的方法中,我希望用户输入,如果它首先通过,而它需要转到第二个while循环,在第二个while循环中,如果条件失败,它需要重新运行循环,而不是重新运行自己,第一个while正在执行 //Method to read, validate and store postcode and purchase amount for N customers public void addRecord(int customerCounter) throws IOException { int po
//Method to read, validate and store postcode and purchase amount for N customers
public void addRecord(int customerCounter) throws IOException
{
int postcode;
double purchaseAmount;
int conform =0;
do{
BufferedReader breader= new BufferedReader(new InputStreamReader(System.in));
System.out.print("Postcode: ");
postcode= Integer.parseInt(breader.readLine());
if(4121 >postcode)
{
System.out.print("Postcode must be greater than 4121");
System.out.print("Try again: ");
}
else if(postcode > 4123)
{
System.out.print("Postcode must be less than 4123");
System.out.print("Try again: ");
}
else
{
conform = 1;
//System.out.println(conform);
}
}
while(4121 >postcode && postcode > 4123);
if(conform == 1)
{
System.out.println(conform);
do
{
BufferedReader breader2= new BufferedReader(new InputStreamReader(System.in));
breader2= new BufferedReader(new InputStreamReader(System.in));
System.out.println("Purchase Amount: ");
purchaseAmount= Double.parseDouble(breader2.readLine());
if(purchaseAmount < 60)
{
System.out.print("Purchase Amount must be greater than $60");
System.out.print("Try again: ");
continue;
}
else if(purchaseAmount > 500)
{
System.out.print("Purchase Amount must be greater than $500");
System.out.print("Try again: ");
}
}
while(purchaseAmount < 60 && purchaseAmount > 500);
}
}
//读取、验证和存储N个客户的邮政编码和购买金额的方法
public void addRecord(int customerCounter)引发IOException
{
国际邮政编码;
购买量加倍;
int=0;
做{
BufferedReader breader=新的BufferedReader(新的InputStreamReader(System.in));
系统输出打印(“邮政编码:”);
postcode=Integer.parseInt(breader.readLine());
如果(4121>邮政编码)
{
系统输出打印(“邮政编码必须大于4121”);
System.out.print(“重试:”;
}
其他条件(邮政编码>4123)
{
系统输出打印(“邮政编码必须小于4123”);
System.out.print(“重试:”;
}
其他的
{
一致=1;
//系统输出打印LN(符合);
}
}
而(4121>邮政编码&&postcode>4123);
如果(符合==1)
{
系统输出打印LN(符合);
做
{
BufferedReader breader2=新的BufferedReader(新的InputStreamReader(System.in));
breader2=新的BufferedReader(新的InputStreamReader(System.in));
系统输出打印项次(“采购金额:”);
purchaseAmount=Double.parseDouble(breader2.readLine());
如果(购买量<60)
{
系统输出打印(“购买金额必须大于$60”);
System.out.print(“重试:”;
继续;
}
否则,如果(采购量>500)
{
系统输出打印(“购买金额必须大于500美元”);
System.out.print(“重试:”;
}
}
而(采购量<60和采购量>500);
}
}
最好的解决方案是使用两个嵌套的无限循环
通过这种方式,程序只检查每个循环插入的邮政编码和价格的2倍,以确定是否可以继续,而不是在您的解决方案中检查4倍
//Method to read, validate and store postcode and purchase amount for N customers
public void addRecord(int customerCounter) throws IOException
{
int postcode;
double purchaseAmount;
int conform =0;
do{
BufferedReader breader= new BufferedReader(new InputStreamReader(System.in));
System.out.print("Postcode: ");
postcode= Integer.parseInt(breader.readLine());
if(4121 >postcode)
{
System.out.print("Postcode must be greater than 4121");
System.out.print("Try again: ");
}
else if(postcode > 4123)
{
System.out.print("Postcode must be less than 4123");
System.out.print("Try again: ");
}
else
{
System.out.println(conform);
do{
BufferedReader breader2= new BufferedReader(new InputStreamReader(System.in));
breader2= new BufferedReader(new InputStreamReader(System.in));
System.out.println("Purchase Amount: ");
purchaseAmount= Double.parseDouble(breader2.readLine());
if(purchaseAmount < 60)
{
System.out.print("Purchase Amount must be greater than $60");
System.out.print("Try again");
continue;
}
else if(purchaseAmount > 500)
{
System.out.print("Purchase Amount must be greater than $500");
System.out.print("Try again");
}else{
break;
}
}while(true);
break;
}
}
while(true);
}
//读取、验证和存储N个客户的邮政编码和购买金额的方法
public void addRecord(int customerCounter)引发IOException
{
国际邮政编码;
购买量加倍;
int=0;
做{
BufferedReader breader=新的BufferedReader(新的InputStreamReader(System.in));
系统输出打印(“邮政编码:”);
postcode=Integer.parseInt(breader.readLine());
如果(4121>邮政编码)
{
系统输出打印(“邮政编码必须大于4121”);
System.out.print(“重试:”;
}
其他条件(邮政编码>4123)
{
系统输出打印(“邮政编码必须小于4123”);
System.out.print(“重试:”;
}
其他的
{
系统输出打印LN(符合);
做{
BufferedReader breader2=新的BufferedReader(新的InputStreamReader(System.in));
breader2=新的BufferedReader(新的InputStreamReader(System.in));
系统输出打印项次(“采购金额:”);
purchaseAmount=Double.parseDouble(breader2.readLine());
如果(购买量<60)
{
系统输出打印(“购买金额必须大于$60”);
系统输出打印(“重试”);
继续;
}
否则,如果(采购量>500)
{
系统输出打印(“购买金额必须大于500美元”);
系统输出打印(“重试”);
}否则{
打破
}
}虽然(正确);
打破
}
}
虽然(正确);
}
您在中的条件虽然是错误的,但总是错误的
postcode = 5000;
while(postcode < 4121 && postcode > 4123); -> while(false && true); -> false
postcode = 3000;
while(postcode < 4121 && postcode > 4123); -> while(true && false); -> false
postcode=5000;
而(邮政编码<4121&&postcode>4123);->while(假&真);->假的
邮政编码=3000;
而(邮政编码<4121&&postcode>4123);->while(真与假);->假的
使用或代替和
while(postcode < 4121 || postcode > 4123);
while(邮政编码<4121 | |邮政编码>4123);
第二段时间也是如此
第一个while的第二次执行可能是因为您再次调用了addRecord
实际上,每件事都是按照要求运行的,我唯一的问题是,当第二个while与条件匹配时,每个都从一开始就开始,而不是只询问purchaseamount我尝试了您提供的样品,但当我输入错误的价格时,它又从第一个循环开始。为了说明这一点,我的要求是,如果用户输入错误的价格,程序应该显示价格屏幕,而不是从一开始就启动。而我的状态总是显示为false。谢谢