我正在尝试使用国际标准字母/数字映射将每个字母替换为数字。我的输出可以正常运行,但是如何让电话号码中的破折号自动出现在输出中?例如,如果我输入 1800Flowers,它会打印为 18003569377。如何在不使用正则表达式的情况下将其打印为 1-800-3569377?
import java.util.Scanner;
public class PhoneKeypad {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
//while loop keeps the program running until the user enters quit
while (true) {
System.out.println("\nEnter a phone number or quit to exit:");
String phoneNumber = input.next();
if (phoneNumber.equalsIgnoreCase("quit")) {
System.out.print("\nProgrammed by me");
return;
}
//checks if the phone number entered is at least 8 digits
if (phoneNumber.length() < 8) {
System.out.println("Invalid Phone Number");
} else {
System.out.println(getNumber(phoneNumber));
}
}
}
//method converts all letters in the phone number to digits
public static String getNumber(String phoneNumber) {
int keypadNum = 0;
for (int i = 0; i < phoneNumber.length(); i++) {
char letter = phoneNumber.charAt(i);
if (Character.isAlphabetic(letter)) {
letter = Character.toUpperCase(letter);
switch (letter) {
case 'A':
case 'B':
case 'C':
keypadNum = 2;
break;
case 'D':
case 'E':
case 'F':
keypadNum = 3;
break;
case 'G':
case 'H':
case 'I':
keypadNum = 4;
break;
case 'J':
case 'K':
case 'L':
keypadNum = 5;
break;
case 'M':
case 'N':
case 'O':
keypadNum = 6;
break;
case 'P':
case 'Q':
case 'R':
case 'S':
keypadNum = 7;
break;
case 'T':
case 'U':
case 'V':
keypadNum = 8;
break;
case 'W':
case 'X':
case 'Y':
case 'Z':
keypadNum = 9;
break;
default:
System.out.println("Invalid phone number");
}
phoneNumber = phoneNumber.substring(0, i) + keypadNum + phoneNumber.substring(i + 1);
}
}
return phoneNumber;
}
}
最佳答案
您可以将正则表达式 与String.replaceAll
一起使用。删除前导一个,将前三位数字、第二位三位数字和最后一组数字分组。有点像
public static String formatNumber(String phoneNumber) {
if (phoneNumber.startsWith("1")) {
phoneNumber = phoneNumber.substring(1);
}
return phoneNumber.replaceAll("(\\d{3})(\\d{3})(\\d+)", "1-$1-$2-$3");
}
或
public static String formatNumber(String phoneNumber) {
return phoneNumber.replaceAll("1(\\d{3})(\\d{3})(\\d+)", "1-$1-$2-$3");
}
然后像这样调用它
System.out.println(formatNumber(getNumber(phoneNumber)));
我用 1800flowers
运行它并得到(如预期的那样)
1-800-356-9377
或没有像
这样的正则表达式public static String formatNumber(String phoneNumber) {
if (phoneNumber.startsWith("1")) {
phoneNumber = phoneNumber.substring(1);
}
return "1-".concat(phoneNumber.substring(0, 3)) //
.concat("-").concat(phoneNumber.substring(3, 6)) //
.concat("-").concat(phoneNumber.substring(6));
}
在调用 formatNumber
之前,您可以删除破折号以规范化它
public static String removeDashes(String phoneNumber) {
StringBuilder sb = new StringBuilder();
for (char ch : phoneNumber.toCharArray()) {
if (ch != '-') {
sb.append(ch);
}
}
return sb.toString();
}
然后
System.out.println(formatNumber(removeDashes(getNumber(phoneNumber))));
关于java - 将电话号码中的所有字母转换为数字,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/41081829/