替換字符串中的char值（Java）

Question

在我的作業中，我需要獲得以下輸出：

輸入一個詞：房子
您要替換什么字母？：e
您想用什么字母代替？ w
新詞是housw。

_____________________________________________。

我讓程序可以使用此代碼，但現在需要設置while循環。 這是我當前的代碼。

字串=“”; 掃描儀鍵盤=新的Scanner（System.in）;

    System.out.print("Enter a word: " + word);
    word = keyboard.nextLine();

    String readChar = null;
    System.out.print("What letter do you want to replace?: ");
    readChar = keyboard.next();

    String changeChar;
    System.out.print("With what letter do you wish to replace it? ");
    changeChar = keyboard.next();

    keyboard.close();
    System.out.println(word.replaceAll(readChar, changeChar));

    System.out.println();

---

我現在需要使程序輸出如下：

輸入一個詞：房子
您要替換什么字母？：
沒有房子。
您要替換什么字母？：b
沒有房子。
您要替換什么字母？：e
您想用什么字母代替？ w
新詞是housw。

---

我的while循環如何描繪此輸出？

Answer 1

讀取單詞和要替換的字符（以及要替換為的字符）后，可以使用String類中的replace方法。

這是用法示例（使變量名適應您的代碼）

word = word.replace(letterToReplace, replacementLetter);

所以舉個例子

String word = "aba";
word = word.replace('a', 'c');
System.out.println(word); // Prints out 'cbc'

另外，這里是到JavaDoc的強制鏈接，用於replace方法：

http://docs.oracle.com/javase/7/docs/api/java/lang/String.html#replace%28char,%20char%29

Answer 2

希望您不要介意進行解釋，下面是可以遵循的示例。

 String a = "HelloBrother How are you!";
 String r = a.replace("HelloBrother","Brother");

 print.i(r);

Answer 3

如果要替換所有字母，可以這樣操作（工作代碼）：

public static void main(String[] args) {

    String word = "";
    Scanner keyboard = new Scanner(System.in);

    System.out.print("Enter a word: " + word);
    word = keyboard.nextLine();

    String readChar = null;
    System.out.print("What letter do you want to replace?: ");
    readChar = keyboard.next();

    String changeChar;
    System.out.print("With what letter do you wish to replace it? ");
    changeChar = keyboard.next();

    keyboard.close();
    System.out.println(word.replace(readChar, changeChar));
}

Answer 4

好的，這是實現問題的第二部分的一種可能方法：

public static void main(String[] args) {

    String word = "";
    Scanner keyboard = new Scanner(System.in);

    System.out.print("Enter a word: " + word);
    word = keyboard.nextLine();

    boolean done = false;
    do{
        String readChar = null;
        System.out.print("What letter do you want to replace?: ");
        readChar = keyboard.next();

        if(word.contains(readChar)){

            String changeChar;
            System.out.print("With what letter do you wish to replace it? ");
            changeChar = keyboard.next();

            done = true;
            keyboard.close();
            System.out.println(word.replace(readChar, changeChar));
        }
    }
    while(!done);
}

Answer 5

這說明了您需要執行的操作。

import java.util.Scanner;
public class WordScrambler{

    public static void main(String[] args) {

    Scanner keyboard = new Scanner(System.in);

    System.out.print("Enter a word: ");
    String word = keyboard.nextLine();

    System.out.print("What letter do you want to replace?: ");
    char letter = keyboard.next().charAt(0);

    StringBuffer out = new StringBuffer(word);
    System.out.print("With what letter do you wish to replace it? ");
    char changeChar = keyboard.next().charAt(0);

    for (int i=0; i<word.length(); ++i) 
        if(word.charAt(i) == changeChar)
            out.setCharAt(i, changeChar);

    System.out.println("The new word is "+out);
    }
}