Java StringBuffer deleteCharAt()方法及实例

Java.lang.StringBuffer.deleteCharAt()是一个内置的Java方法，它可以删除这个序列中指定位置上的字符。这样，该序列就减少了1个字符。

语法

public StringBuffer deleteCharAt(int indexpoint)

参数： 该方法接受一个整数类型的参数indexpoint，它指的是要删除的字符的索引。
返回值： 该函数返回字符串或在删除字符后返回这个对象。
异常： 如果indexpoint是负数或大于等于length()，那么该方法抛出StringIndexOutOfBoundsException。

例子

Input : StringBuffer = worldofgeeks
        int indexpoint = 4
Output : worlofgeeks

下面的程序说明了StringBuffer.deleteCharAt()方法的工作情况：
程序1 :

// Java program to demonstrate working
// of StringBuffer.deleteCharAt() method
  
import java.lang.*;
  
public class Geeks {
  
    public static void main(String[] args)
    {
  
        StringBuffer sbf = new StringBuffer("raghav");
        System.out.println("String buffer before deletion = " + sbf);
  
        // Deleting the character at indexpoint 5
        sbf.deleteCharAt(5);
        System.out.println("After deletion new StringBuffer = " + sbf);
    }
}

输出

String buffer before deletion = raghav
After deletion new StringBuffer = ragha

程序2

// Java program to demonstrate working
// of StringBuffer.deleteCharAt() method
  
import java.lang.*;
  
public class Geeks {
  
    public static void main(String[] args)
    {
  
        StringBuffer sbf = new StringBuffer("GeeksforGeeks");
        System.out.println("String buffer before deletion = " + sbf);
  
        // Deleting the character at indexpoint 5
        sbf.deleteCharAt(5);
        System.out.println("After deletion new StringBuffer = " + sbf);
    }
}

输出

String buffer before deletion = GeeksforGeeks
After deletion new StringBuffer = GeeksorGeeks

计划3 。

// Java program to demonstrate working
// of StringBuffer.deleteCharAt() method
  
import java.lang.*;
  
public class Geeks {
  
    public static void main(String[] args)
    {
  
        StringBuffer sbf = new StringBuffer("Abhishek");
        System.out.println("String buffer before deletion = " + sbf);
  
        // Deleting the character at indexpoint -5
        sbf.deleteCharAt(-5);
        System.out.println("After deletion new StringBuffer = " + sbf);
    }
}

输出

Exception in thread "main" java.lang.StringIndexOutOfBoundsException: 
                                             String index out of range: -5
    at java.lang.AbstractStringBuilder.deleteCharAt
                                          (AbstractStringBuilder.java:824)
    at java.lang.StringBuffer.deleteCharAt(StringBuffer.java:441)
    at Geeks.main(Geeks.java:14)