用for循环将英语翻译成莫尔斯电码

Question

我已彻底搜索，但在此站点上找不到满意的答案。 我的任务是将一串英文大写字符翻译成莫尔斯电码。

我的计划是遍历字符串并将数组中 (i) 的索引与具有摩尔斯电码索引的字母匹配。

import java.util.Scanner;

public class Morse { 
    public static void main(String[]arg) {
        Scanner Read = new Scanner(System.in);
        String uinput, res = "";

        String[] Eng = {"A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","X","Y","Z"};
        String[] mors = {".-","-...","-.-.","-..",".","..-.","--.","....","..",".---","-.-",".-..","--","-.","---",".--.","--.-",".-.","...","-","..-","...-",".--","-..-","-.--","--.."};

        System.out.println("Ange den text du vill översätta till Morse-kod: ");
        uinput = Read.nextLine();  //uinput = user input 
        for (int i = 0; i < uinput.length(); ) {
            res = res + (mors.charAt(Eng.indexOf(i)));
        }
        System.out.println(res);
    }
}

当我运行它时，我收到错误消息：

Morse.java:16: error: cannot find symbol
  res = res + (mors.charAt(Eng.indexOf(i)));
                                  ^
  symbol:   method indexOf(int)
  location: variable Eng of type String[]
1 error

Answer 1

你有两个问题。

首先，您没有查看来自uinput 本身的字符。您需要遍历这些字符来构建您的输出。

第二个是Java的内置数组没有indexOf()方法。您有几种选择：

1. 你可以自己写一个。
2. 您可以将 Eng 数组的内容放入一个 List（可能是 ArrayList）中，它确实具有 indexOf() 方法。
3. 由于 Java char 也是数字，您可以将字母本身用作摩尔斯电码数组的索引。 （但要注意大小写问题，并注意“A”的数值不是 0。）

Answer 2

您似乎正在尝试对数组使用 String 方法。我认为正确的方法是遍历数组并检查每个数组的字符。即替换：

  for (int i=0; i<uinput.length();)
  {
  res = res + (mors.charAt(Eng.indexOf(i)));
  }

有了类似的东西：

for (int i=0; i<uinput.length(); i++)
{
    for(int j=0; j<Eng.length(); j++){
        if(uipunt.charAt(i) == Eng[j]) {
           res = res + (mors[j]);
           continue;
        }
    }
}

这没有经过测试，但希望能让你走上正确的道路

Answer 3

您看到的错误是调用不存在的方法的结果。使用方括号 [] 引用数组。要获得索引 i，我们会说：

Eng[i]

就我个人而言，我会尊重 ASCII 代码来识别 mores 代码的索引。在这种情况下，字母“A”在 ASCII 中是 65。 “A”是数组中的索引零。所以索引 char 的 ASCII 值（大写）减去 65。

import java.util.Scanner;

public class MorseCode {

    private static final String[] MORS = { ".-", "-...", "-.-.", "-..", ".",
            "..-.", "--.", "....", "..", ".---", "-.-", ".-..", "--", "-.",
            "---", ".--.", "--.-", ".-.", "...", "-", "..-", "...-", ".--",
            "-..-", "-.--", "--.." };

    public static void main(String... args) {

        try (Scanner read = new Scanner(System.in)) {

            System.out.print("Morse-Code It (type \"exit\" to exit): ");

            String text = "";
            while (!"exit".equals(text.toLowerCase())) {
                text = removeNonLetters(read.nextLine());
                System.out.println(toMors(text));
            }
        }
    }

    private static String removeNonLetters(String str) {
        return str.replaceAll("[^A-Za-z]", "");
    }

    private static int getIndex(char c) {
        return Character.toUpperCase(c)-65;
    }

    private static String toMors(String str) {
        StringBuilder sb = new StringBuilder();

        for (int i = 0; i < str.length(); i++) {
            sb.append(MORS[getIndex(str.charAt(i))]);
            sb.append("   ");
        }

        return sb.toString();
    }
}

Answer 4

charAt 不是调用字符串数组的有效方法。使用 ArrayList 而不是数组，您应该能够使用 index of。

Answer 5

我要感谢大家的回答，他们帮助我创建了最终代码：

import java.util.Scanner;
public class Morse
{ 
 public static void main(String[]arg)
 {
  Scanner Read = new Scanner(System.in);
  String uinput,utskr = "";


  String[] letters = {"A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","X","Y","Z"};
  String[] mors = {".-","-...","-.-.","-..",".","..-.","--.","....","..",".---","-.-",".-..","--","-.","---",".--.","--.-",".-.","...","-","..-","...-",".--","-..-","-.--","--.."};
  System.out.println("Ange den text du vill översätta till Morse-kod: ");
  uinput = Read.nextLine();
  for (int i=0; i<uinput.length();)
  {
  char currentChar = uinput.charAt(i);
  int charIndex = letters.indexOf(currentChar);
  utskr = utskr + mors[charIndex] + " ";
  }

  System.out.println(utskr);

 }
}

Answer 6

Java 代码

import java.io.BufferedWriter;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.FileWriter;
import java.io.IOException;
import java.io.ObjectOutputStream;
import java.io.ObjectInputStream.GetField;
import java.lang.reflect.Array;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashMap;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.Map;
import java.util.Random;
import java.util.Scanner;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class TestProgram {

    public static HashMap<String, String> alphaMorse = new HashMap<String, String>();

    public static void main(String[] args) throws FileNotFoundException {
        // TODO Auto-generated method stub
        alphaMorse.put("A", ".-");
        alphaMorse.put("B", "-...");
        alphaMorse.put("C", "-.-.");
        alphaMorse.put("D", "-..");
        alphaMorse.put("E", ".");
        alphaMorse.put("F", "..-.");
        alphaMorse.put("G", "--.");
        alphaMorse.put("H", "....");
        alphaMorse.put("I", "..");
        alphaMorse.put("J", ".---");
        alphaMorse.put("K", "-.-");
        alphaMorse.put("L", ".-..");
        alphaMorse.put("M", "--");
        alphaMorse.put("N", "-.");
        alphaMorse.put("O", "---");
        alphaMorse.put("P", ".--.");
        alphaMorse.put("Q", "--.-");
        alphaMorse.put("R", ".-.");
        alphaMorse.put("S", "...");
        alphaMorse.put("T", "-");
        alphaMorse.put("U", "..-");
        alphaMorse.put("V", "...-");
        alphaMorse.put("W", ".--");
        alphaMorse.put("X", "-..-");
        alphaMorse.put("y", "-.--");
        alphaMorse.put("z", "--..");
        alphaMorse.put("1", ".----");
        alphaMorse.put("2", "..---");
        alphaMorse.put("3", "...--");
        alphaMorse.put("4", "....-");
        alphaMorse.put("5", ".....");
        alphaMorse.put("6", "-....");
        alphaMorse.put("7", "--...");
        alphaMorse.put("8", "---..");
        alphaMorse.put("9", "----.");
        alphaMorse.put("0", "-----");
        alphaMorse.put(" ", "|");

        String st = "hello";

    String morse="";
        String convertedMorseCode=toMors(st);
        System.out.print(convertedMorseCode);
    }

    public static String toMors(String st){
        String morse="";

        for (int i = 0; i < st.length(); i++) {
            char c =st.charAt(i);

            char charUpper = Character.toUpperCase(c);
            String morseCode= alphaMorse.get(Character.toString(charUpper));
            //System.out.println(morseCode);
            morse=  morse+morseCode;

        }
        return morse;
    }
}