如何从字符串中删除一个字符

Question

使用扫描仪，我想读取char的索引，然后将其从字符串中删除。只有一个问题：如果char在字符串中出现多次，那么。替换（）将删除所有这些字符。

例如，我想从字符串“纹理文本”中获取第一个“t”的索引，然后只删除那个“t”。然后我想得到第二个't'的索引，然后删除它。

import java.util.Scanner;

class Main {
  public static void main(String[] args) {
   String text = "Texty text";
   Scanner sc = new Scanner(System.in);
   int f = 0;
   int x = 0;
   while(f<1){
   char c = sc.next().charAt(0);
    for(int i = 0; i<text.length();i++){

      if(text.charAt(i)==c){

        System.out.println(x);
        x++;
      }
      else{
        x++;
      }

    }
  }
   System.out.println(text);
  }
}

Answer 1

尝试使用txt。子串（x，y）

x=通常为0，但x是第一个开始索引y=这是您要删除的内容，例如，为字符串的最后一个字编写以下代码：txt。子字符串（0，txt.length（）-1）

Answer 2

可能您正在寻找以下内容：

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        String text = "Texty text";
        String copy = text;
        Scanner sc = new Scanner(System.in);
        while (true) {
            text = copy;
            System.out.print("Enter a character from '" + text + "': ");
            char c = sc.next().charAt(0);
            for (int i = 0; i < text.length(); i++) {
                if (Character.toUpperCase(text.charAt(i)) == Character.toUpperCase(c)) {
                    System.out.println(c + " was found at " + i);
                    text = text.substring(0, i) + "%" + text.substring(i + 1);
                    System.out.println("After replacing " + c + " with % at " + i + ": " + text);
                }
            }
        }
    }
}

运行示例：

Enter a character from 'Texty text': x
x was found at 2
After replacing x with % at 2: Te%ty text
x was found at 8
After replacing x with % at 8: Te%ty te%t
Enter a character from 'Texty text': t
t was found at 0
After replacing t with % at 0: %exty text
t was found at 3
After replacing t with % at 3: %ex%y text
t was found at 6
After replacing t with % at 6: %ex%y %ext
t was found at 9
After replacing t with % at 9: %ex%y %ex%
Enter a character from 'Texty text': 

Answer 3

您可以使用replaceFirst：

System.out.println(text.replaceFirst("t", ""));