Java中替换字符串中的字符

huangapple
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英文:

Java replace a character in a string

问题

  1. public Boolean isVowel(char ch){
  2.     char ch2 = Character.toLowerCase(ch);
  3.     char[] vowels = {'a', 'e', 'i', 'o', 'u'};
  4.     
  5.     for(int i = 0; i < vowels.length; i++){
  6.         if (ch2 == vowels[i]) {
  7.             return true;
  8.         }
  9.     }
  10.     return false;
  11. }
  13. public String replaceVowels(String phrase, char ch){
  14.     String newP = "";
  15.     for(int i = 0; i < phrase.length(); i++){  
  16.         char c = phrase.charAt(i);
  17.         Boolean vowel = isVowel(c);
  18.         
  19.         if(vowel){ 
  20.            newP = phrase.replace(c, ch);
  21.         }
  22.     }
  23.     return newP;
  24. }
英文:

I am writing a method to replace all vowels in a string with a given character, but it does not work for strings with more than one vowel. It works for "heel" but not for "hello". Please help. My code below:

  1. public Boolean isVowel(char ch){
  2.         
  3.         char ch2 = Character.toLowerCase(ch); 
  4.         char[] vowels = {&#39;a&#39;, &#39;e&#39;, &#39;i&#39;, &#39;o&#39;, &#39;u&#39;};
  5.         
  6.         for(int i = 0; i &lt; vowels.length; i++){
  7.             if (ch2 == vowels[i]) {
  8.                 return true;
  9.             }
  10.         }
  11.             return false;
  12.     }
  13.     
  14.     public String replaceVowels(String phrase, char ch){
  15.         String newP = &quot;&quot;;
  16.         for(int i = 0; i &lt; phrase.length(); i++){  
  17.             char c = phrase.charAt(i);
  18.             Boolean vowel = isVowel(c);
  19.             
  20.             if(vowel){ 
  21.                newP = phrase.replace(c, ch);
  22.             }
  23.         }
  24.         
  25.         return newP;
  26.     }

答案1

得分: 6

  1. public String replaceVowels(final String phrase, final String ch) {
  2.     return phrase.replaceAll("[aeiou]", ch);
  3. }
英文: 
  1. public String replaceVowels(final String phrase,final String ch) {
  2.     return phrase.replaceAll(&quot;[aeiou]&quot;, ch);
  3. }

答案2

得分: 2

这是一种用 Java 字符替换字符串中所有元音字母的方法。其中的 (?i) 表示不区分大小写。"" +ch 从字符中获取一个字符串。

  1. String str = &quot;hEllo&quot;;
  2. char ch = &#39;X&#39;;
  3. str = str.replaceAll( &quot;(?i)[aeiou]&quot;, &quot;&quot; +ch );

也可以更明确地区分大小写，如下：

  1. String str = &quot;hEllo&quot;;
  2. char ch = &#39;X&#39;;
  3. str = str.replaceAll( &quot;[aeiouAEIOU]&quot;, &quot;&quot; +ch );
英文:

Here is one way to replace all vowels in a string with an java char. The (?i) is to make it case insensitive. The "" +ch gets a string from the char.

  1. String str = &quot;hEllo&quot;;
  2. char ch = &#39;X&#39;;
  3. str = str.replaceAll( &quot;(?i)[aeiou]&quot;, &quot;&quot; +ch );

Could also be more explicit with case like:

  1. String str = &quot;hEllo&quot;;
  2. char ch = &#39;X&#39;;
  3. str = str.replaceAll( &quot;[aeiouAEIOU]&quot;, &quot;&quot; +ch );

答案3

得分: 1

你的问题在于 newP = phrase.replace(c, ch); 你正在赋予一个最终值。

  1. String newP = phrase;
  2.         for(int i = 0; i < phrase.length(); i++){
  3.             char c = phrase.charAt(i);
  4.             Boolean vowel = isVowel(c);
  6.             if(vowel){
  7.                 newP = newP.replace(c, ch);
  8.             }
  9.         }

根据Alex的回答，更好的解决方案是添加 String：

  1. phrase.replaceAll("[aeiou]", "" + ch);
英文:

Your problem is newP = phrase.replace(c, ch); You are assigning a last value.

  1. String newP = phrase;
  2.         for(int i = 0; i &lt; phrase.length(); i++){
  3.             char c = phrase.charAt(i);
  4.             Boolean vowel = isVowel(c);
  6.             if(vowel){
  7.                 newP = newP.replace(c, ch);
  8.             }
  9.         }

Better solution as answered by Alex just add String,

  1. phrase.replaceAll(&quot;[aeiou]&quot;, &quot;&quot;+ch);

huangapple
  • 本文由 发表于 2020年4月4日 20:33:33
  • 转载请务必保留本文链接：https://go.coder-hub.com/61028144.html
  • algorithm
  • java
  • string
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