简单Java银行Atm登录循环错误
第一次发帖，这里的人似乎很有帮助。 我目前正在编写我的第二份简单银行atm/账户作业。我的用户pin登录代码没有执行以下操作 1。在阵列中找不到管脚时返回到循环的开始处 2。如果pin不正确，使程序停止 以下是登录脚本的片段。问题在于简单Java银行Atm登录循环错误,java,bank,Java,Bank,第一次发帖，这里的人似乎很有帮助。 我目前正在编写我的第二份简单银行atm/账户作业。我的用户pin登录代码没有执行以下操作 1。在阵列中找不到管脚时返回到循环的开始处 2。如果pin不正确，使程序停止 以下是登录脚本的片段。问题在于while（menuChoice==1）{}循环 public static void main(String args[]) { Scanner in = new Scanner(System.in); boolean userLogin = f
while（menuChoice==1）{}public static void main(String args[]) {
Scanner in = new Scanner(System.in);
boolean userLogin = false; //Flag for user login authorization
boolean progOn=true; //confirmation that program is still be running
int num = 0, i = 0;
int Bal[] = {500, 250, 400, 700};
String Names[] = {"Niall", "Sean", "John", "Connor"};
String pin[] = {"1234", "2345", "3456", "4567"};
String menu2 = "\n1. Deposit \n2. Withdrawal \n3. Balance \n4: Change pin \n5: Exit";
String pinChoice = "", pinChange="";
int sub = 0; //To keep the subscript
String startMenu = ""; //The entered choice for the Start menu as a string
int menuChoice = 0; //The entered choice for the menu as an int
//--------------------
//login script
//--------------------
while (progOn == true) {
System.out.println("------------------------");
System.out.println("Welcome! Please select an option...\n");
System.out.println(">1. Login");
System.out.println(">2. Quit");
System.out.println("------------------------");
startMenu = in.next();
while (!startMenu.matches("[1-2]")) { //If the user enters a non digit, give message and return
System.out.println("\nError. Please enter a valid Menu option.\n");
System.out.println(">1. Login");
System.out.println(">2. Quit");
System.out.print("Please select an option\n"); //Ask the user to choose again
startMenu = in.next();
}//end while loop
menuChoice = Integer.parseInt(startMenu); //Parse the string to an int
while (menuChoice == 1) { //While loop to carry out the users choice
System.out.println("------------------------");
System.out.println("Please enter your pin number: ");
System.out.println("------------------------");
pinChoice = in.next();
while (!pinChoice.matches("\\d{4}")) { // 4 numbers only message to the user, if number is shorter or longer than 4
System.out.println("------------------------");
System.out.println("Error, must be a 4 number pin only! Please retry:");
System.out.println("------------------------");
pinChoice = in.next();
}
for (i = 0; i < Names.length; i++) {
//Check if PIN exists
if (pinChoice.matches(pin[i])) {
userLogin = true; //If the PIN exists (true) the user is brought to the main menu
System.out.println("------------------------");
System.out.println("Please select a option from the menu...");
sub = i; //sub is the array number stored of that account
}//end if PIN matches
}
if (userLogin == false) { //If the PIN doesn't exist
System.out.print("\nPin does not exist\n\n"); //Tell the user and bring them back to the main menu
}//end if no user found
break;
}// end loop menuChoic == 1
while (menuChoice == 2) { //user chooses to Leave the program
System.out.print("\nThank you, goodbye\n");
System.exit(0); //Exits the program
break;
}//end menuChoice==2
//--------------------
//end login script
//--------------------
}
}
publicstaticvoidmain（字符串参数[]）{
扫描仪输入=新扫描仪（系统输入）；
布尔userLogin=false；//用户登录授权标志
boolean progOn=true；//确认程序仍在运行
int num=0，i=0；
int Bal[]={500250400700}；
字符串名[]={“尼尔”、“肖恩”、“约翰”、“康纳”}；
字符串引脚[]={“1234”、“2345”、“3456”、“4567”}；
字符串menu2=“\n1.存款\n2.取款\n3.余额\n4:更改pin码\n5:退出”；
字符串pinChoice=“”，pinChange=“”；
int sub=0；//保留下标
String startMenu=“”；//作为字符串输入的开始菜单选项
int menuChoice=0；//输入的菜单选项为int
//--------------------
//登录脚本
//--------------------
while（progOn==true）{
System.out.println（“---------------------------”）；
System.out.println（“欢迎！请选择一个选项…\n”）；
System.out.println（“>1.Login”）；
System.out.println（“>2.Quit”）；
System.out.println（“---------------------------”）；
startMenu=in.next（）；
而（！startMenu.matches（“[1-2]”））{//如果用户输入非数字，则给出消息并返回
System.out.println（“\n错误。请输入有效的菜单选项。\n”）；
System.out.println（“>1.Login”）；
System.out.println（“>2.Quit”）；
System.out.print（“请选择一个选项”；//请用户再次选择
startMenu=in.next（）；
}//边结束边循环
menuChoice=Integer.parseInt（startMenu）；//将字符串解析为int
while（menuChoice==1）{//while循环执行用户选择
System.out.println（“---------------------------”）；
System.out.println（“请输入您的pin码：”）；
System.out.println（“---------------------------”）；
pinChoice=in.next（）；
而（！pinChoice.matches（“\\d{4}”）{//4只向用户发送数字消息，如果数字小于或大于4
System.out.println（“---------------------------”）；
System.out.println（“错误，只能是4号pin！请重试：”）；
System.out.println（“---------------------------”）；
pinChoice=in.next（）；
}
对于（i=0；i谢谢你的关注！：） while循环条件是
while（menuChoice==1）menuChoicemenuChoice中断引脚不存在的部分中的行，以便在达到该逻辑时，可以退出循环
我认为最干净的解决办法是移动你的断点在if条件下的touserLogin==false
祝你好运 更换
if (pinChoice.matches(pin[i]))
与
要检查夹选是否等于阵列元素，请使用等于方法
此外，for循环的迭代如下所示：
for (i = 0; i < Names.length; i++)
for（i=0；i
必须迭代到pin
数组的大小而不是Names
length在循环中，应该使用局部变量。你有一个全局变量
int i;
尝试将循环中的i更改为int ii
for (int ii = 0; ii < Names.length; ii++) {
//Check if PIN exists
if (pinChoice.matches(pin[ii])) {
userLogin = true; //If the PIN exists (true) the user is brought to the main menu
System.out.println("------------------------");
System.out.println("Please select a option from the menu...");
sub = ii; //sub is the array number stored of that account
}//end if PIN matches
}
for（int ii=0；ii
整整两个小时后，我终于明白了这一点，并在登录过程中添加了一个额外的步骤
public static void main(String args[]) {
Scanner in = new Scanner(System.in);
boolean userLogin = false; //Flag for user login authorization
boolean progOn=true; //confirmation that program is still be running
int num=0;
int Bal[] = {500,250,400,700};
String Names[]={"Niall", "Chris", "John", "Connor"};
String pin[]= {"1111","2222","3333","4444"};
String menu2= "\n1. Deposit \n2. Withdrawal \n3. Balance \n4: Change pin \n5: Exit";
String pinChoice = "", pinChange="", strNameChoice="", startMenu="";
int sub=0, sub2=0; //To keep a subscript
int menuChoice=0 ; //The entered choice for the menu and name as an int
int nameChoice=0;
//--------------------
//login script
//--------------------
while(progOn==true){
System.out.println("------------------------");
System.out.println("Welcome! Please select an option...\n>1. Login\n>2. Quit");
System.out.println("------------------------");
startMenu=in.next();
while(!startMenu.matches("[1-2]")){ //If the user enters a non digit, give message and return
System.out.println("\nError. Please enter a valid Menu option.\n>1. Login\n>2. Quit\nPlease select an option\n"); //Ask the user to choose again
startMenu=in.next();
}//end while loop
menuChoice=Integer.parseInt(startMenu); //Parse the string to an int
while(userLogin==false){ // loop to verify that the login is correct, and a rest point.
while(menuChoice==1){ //While loop to carry out the users choice
System.out.println("------------------------");//User name selection
System.out.println("Please select the number of your user name. \n1> " +Names[0]+"\n2> " +Names[1]+"\n3> " +Names[2]+"\n4> " +Names[3]);
System.out.println("------------------------");
strNameChoice=in.next();
while(!strNameChoice.matches("[1-4]")){ // 4 numbers only message to the user, if number is shorter or longer than 4
System.out.println("------------------------");
System.out.println("Error, must be a one of the 4 numbers only! Please retry:");
System.out.println("------------------------");
strNameChoice=in.next();
}
nameChoice=Integer.parseInt(strNameChoice);
sub2=nameChoice-1;
System.out.println("------------------------"); //PIN ENTRY
System.out.print("Please enter your Pin\n");
pinChoice = in.next();
while(!pinChoice.matches("\\d+")){
System.out.print("\nError, digits only\n");
System.out.print("\nEnter your PIN\n>");
pinChoice = in.next();
}//end while PIN is non digits
for(int i=0;i<Names[sub2].length();i++){ //Check if PIN exists inside the loop
if(pinChoice.matches(pin[sub2])){
userLogin = true; //If the PIN exists (true) the user is brought to the main menu
sub = sub2-1; //sub is the array number stored of that account
}//end if PIN matches
}
if(userLogin == false){ //If the PIN doesn't exist
System.out.print("\n------------------------");
System.out.print("\nPin entered is incorrect \nPlease try again \n");
}//end if no user found
break;//Tell the user and bring them back to the main menu
}// end loop menuChoice==1
while(menuChoice==2){ //user chooses to Leave the program
System.out.print("\nThank you, goodbye\n");
System.exit(0); //Exits the program
break;
}//end menuChoice==2
}
//--------------------
//end login script
//--------------------
谢谢你的意见。虽然我知道它应该在for循环中，但它确实没有
public static void main(String args[]) {
Scanner in = new Scanner(System.in);
boolean userLogin = false; //Flag for user login authorization
boolean progOn=true; //confirmation that program is still be running
int num=0;
int Bal[] = {500,250,400,700};
String Names[]={"Niall", "Chris", "John", "Connor"};
String pin[]= {"1111","2222","3333","4444"};
String menu2= "\n1. Deposit \n2. Withdrawal \n3. Balance \n4: Change pin \n5: Exit";
String pinChoice = "", pinChange="", strNameChoice="", startMenu="";
int sub=0, sub2=0; //To keep a subscript
int menuChoice=0 ; //The entered choice for the menu and name as an int
int nameChoice=0;
//--------------------
//login script
//--------------------
while(progOn==true){
System.out.println("------------------------");
System.out.println("Welcome! Please select an option...\n>1. Login\n>2. Quit");
System.out.println("------------------------");
startMenu=in.next();
while(!startMenu.matches("[1-2]")){ //If the user enters a non digit, give message and return
System.out.println("\nError. Please enter a valid Menu option.\n>1. Login\n>2. Quit\nPlease select an option\n"); //Ask the user to choose again
startMenu=in.next();
}//end while loop
menuChoice=Integer.parseInt(startMenu); //Parse the string to an int
while(userLogin==false){ // loop to verify that the login is correct, and a rest point.
while(menuChoice==1){ //While loop to carry out the users choice
System.out.println("------------------------");//User name selection
System.out.println("Please select the number of your user name. \n1> " +Names[0]+"\n2> " +Names[1]+"\n3> " +Names[2]+"\n4> " +Names[3]);
System.out.println("------------------------");
strNameChoice=in.next();
while(!strNameChoice.matches("[1-4]")){ // 4 numbers only message to the user, if number is shorter or longer than 4
System.out.println("------------------------");
System.out.println("Error, must be a one of the 4 numbers only! Please retry:");
System.out.println("------------------------");
strNameChoice=in.next();
}
nameChoice=Integer.parseInt(strNameChoice);
sub2=nameChoice-1;
System.out.println("------------------------"); //PIN ENTRY
System.out.print("Please enter your Pin\n");
pinChoice = in.next();
while(!pinChoice.matches("\\d+")){
System.out.print("\nError, digits only\n");
System.out.print("\nEnter your PIN\n>");
pinChoice = in.next();
}//end while PIN is non digits
for(int i=0;i<Names[sub2].length();i++){ //Check if PIN exists inside the loop
if(pinChoice.matches(pin[sub2])){
userLogin = true; //If the PIN exists (true) the user is brought to the main menu
sub = sub2-1; //sub is the array number stored of that account
}//end if PIN matches
}
if(userLogin == false){ //If the PIN doesn't exist
System.out.print("\n------------------------");
System.out.print("\nPin entered is incorrect \nPlease try again \n");
}//end if no user found
break;//Tell the user and bring them back to the main menu
}// end loop menuChoice==1
while(menuChoice==2){ //user chooses to Leave the program
System.out.print("\nThank you, goodbye\n");
System.exit(0); //Exits the program
break;
}//end menuChoice==2
}
//--------------------
//end login script
//--------------------
while(userLogin==false){ // loop to verify that the login is correct, and a rest point.
while(menuChoice==1){