看，我粘贴了整个代码，因为只有当您看到整个代码时，您才能理解问题。遇到我的问题，我希望该程序接受他的字符串，直到我希望它停止为止
看了好几个小时，我尝试了很多循环，如果您能在此问题上为我提供帮助，我将很高兴
import java.util.*;
class secretopencoding
{
public static void main()
{
Scanner sc=new Scanner(System.in);
System.out.println("Enter a string");
String a = sc.nextLine();
int l = a.length();
int i;
char b;
for (i=0;i<l;i++)
{
b = a.charAt(i);
if (b=='a'||b=='A')
System.out.print("01");
if (b=='b'||b=='B')
System.out.print("02");
if (b=='c'||b=='C')
System.out.print("03");
if (b=='d'||b=='D')
System.out.print("04");
if (b=='e'||b=='E')
System.out.print("05");
if (b=='f'||b=='F')
System.out.print("06");
if (b=='g'||b=='G')
System.out.print("07");
if (b=='h'||b=='H')
System.out.print("08");
if (b=='i'||b=='I')
System.out.print("09");
if (b=='j'||b=='J')
System.out.print("10");
if (b=='k'||b=='K')
System.out.print("11");
if (b=='l'||b=='L')
System.out.print("12");
if (b=='m'||b=='M')
System.out.print("13");
if (b=='n'||b=='N')
System.out.print("14");
if (b=='o'||b=='O')
System.out.print("15");
if (b=='p'||b=='P')
System.out.print("16");
if (b=='q'||b=='Q')
System.out.print("17");
if (b=='r'||b=='R')
System.out.print("18");
if (b=='s'||b=='S')
System.out.print("19");
if (b=='t'||b=='T')
System.out.print("20");
if (b=='u'||b=='U')
System.out.print("21");
if (b=='v'||b=='V')
System.out.print("22");
if (b=='w'||b=='W')
System.out.print("23");
if (b=='x'||b=='X')
System.out.print("24");
if (b=='y'||b=='Y')
System.out.print("25");
if (b=='z'||b=='Z')
System.out.print("26");
if (b==' ')
System.out.print("27");
}
}
}
每次都会问我是否要进入程序并继续运行直到输入no继续直到输入no
答案 0 :(得分：0)
您必须迭代已经拥有的内容，直到用户停止它为止。为此，您可以使用while进行迭代，并停止它，您可以设置一个键，如果将其作为输入引入，它将停止程序。这样，停止while循环的条件就是该input.equals(stopKey)。
我已经评论了新行
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
String a;
// key that indicates the program to stop
String stopKey = "stop";
System.out.println("Enter a string");
while (!(a = sc.nextLine()).equals(stopKey)) { // when input is equal to key, it stops
// nothing changed here ...
int l = a.length();
int i;
char b;
for (i = 0; i < l; i++) {
b = a.charAt(i);
if (b == 'a' || b == 'A')
System.out.print("01");
if (b == 'b' || b == 'B')
System.out.print("02");
if (b == 'c' || b == 'C')
System.out.print("03");
if (b == 'd' || b == 'D')
System.out.print("04");
if (b == 'e' || b == 'E')
System.out.print("05");
if (b == 'f' || b == 'F')
System.out.print("06");
if (b == 'g' || b == 'G')
System.out.print("07");
if (b == 'h' || b == 'H')
System.out.print("08");
if (b == 'i' || b == 'I')
System.out.print("09");
if (b == 'j' || b == 'J')
System.out.print("10");
if (b == 'k' || b == 'K')
System.out.print("11");
if (b == 'l' || b == 'L')
System.out.print("12");
if (b == 'm' || b == 'M')
System.out.print("13");
if (b == 'n' || b == 'N')
System.out.print("14");
if (b == 'o' || b == 'O')
System.out.print("15");
if (b == 'p' || b == 'P')
System.out.print("16");
if (b == 'q' || b == 'Q')
System.out.print("17");
if (b == 'r' || b == 'R')
System.out.print("18");
if (b == 's' || b == 'S')
System.out.print("19");
if (b == 't' || b == 'T')
System.out.print("20");
if (b == 'u' || b == 'U')
System.out.print("21");
if (b == 'v' || b == 'V')
System.out.print("22");
if (b == 'w' || b == 'W')
System.out.print("23");
if (b == 'x' || b == 'X')
System.out.print("24");
if (b == 'y' || b == 'Y')
System.out.print("25");
if (b == 'z' || b == 'Z')
System.out.print("26");
if (b == ' ')
System.out.print("27");
}
// ask for a new input
System.out.println("\nEnter a string");
}
// at this point user have enter the stop key
System.out.println("Stoped. Bye!");
// close the Scanner
sc.close();
}