Java中的StringBuffer insert()

StringBuffer.insert() 方法将给定数据类型的字符串表示形式插入到 StringBuffer 中的给定位置。

句法：

str.insert(int position,  char x);
 str.insert(int position,  boolean x);
 str.insert(int position,  char[] x);
 str.insert(int position, float x);
 str.insert(int position, double x);
 str.insert(int position, long x);
 str.insert(int position, int x);

position is the index in string where
we need to insert.

返回：

This method returns a reference to this object.

例外：

The position argument must be greater
than or equal to 0, and less than 
or equal to the length of this string.

布尔输入

// Java program to demonstrate StringBuffer insert
// for boolean input.  
import java.lang.*;
  
public class GFG {
    public static void main(String[] args)
    {
        StringBuffer str = 
             new StringBuffer("geeks for geeks");
        System.out.println("string = " + str);
  
        // insert boolean value at offset 8
        str.insert(8, true);
  
        // prints stringbuffer after insertion
        System.out.print("After insertion = ");
        System.out.println(str.toString());
    }
}

输出：

string = geeks for geeks
After insertion = geeks fotruer geeks

字符输入

// Java program to demonstrate StringBuffer insert
// for char input.  
import java.lang.*;
  
public class GFG {
    public static void main(String[] args)
    {
        StringBuffer str = 
           new StringBuffer("geeks for geeks");
        System.out.println("string = " + str);
  
        // insert boolean value at offset 8
        str.insert(8, 'p');
  
        // prints stringbuffer after insertion
        System.out.print("After insertion = ");
        System.out.println(str.toString());
    }
}

输出：

string = geeks for geeks
After insertion = geeks fopr geeks

字符数组输入

// Java program to demonstrate StringBuffer insert
// for char array input.  
import java.lang.*;
  
public class GFG {
    public static void main(String[] args)
    {
        StringBuffer str = 
               new StringBuffer("geeks for geeks");
        System.out.println("string = " + str);
  
        // character array to be inserted
        char cArr[] = { 'p', 'a', 'w', 'a', 'n' };
  
        // insert character array at offset 9
        str.insert(8, cArr);
  
        // prints stringbuffer after insertion
        System.out.print("After insertion = ");
        System.out.println(str.toString());
    }
}

输出：

string = geeks for geeks
After insertion = geeks fopawanr geeks

浮点输入

// Java program to demonstrate StringBuffer insert
// for float input.
import java.lang.*;
  
public class GFG 
{
    public static void main(String[] args)
    {
        StringBuffer str =
            new StringBuffer("geeks for geeks");
        System.out.println("string = " + str);
          
        // insert float value at offset 3
        str.insert(8, 41.35f);
          
        // prints stringbuffer after insertion
        System.out.print("After insertion = ");
        System.out.println(str.toString());
   }      
}

输出：

string = geeks for geeks
After insertion = geeks fo41.35r geeks

双输入

// Java program to demonstrate StringBuffer insert
// for double input.
import java.lang.*;
  
public class GFG 
{
    public static void main(String[] args)
    {
        StringBuffer str = 
           new StringBuffer("geeks for geeks");
        System.out.println("string = " + str);
          
        // insert float value at offset 3
        str.insert(8, 41.35d);
          
        // prints stringbuffer after insertion
        System.out.print("After insertion = ");
        System.out.println(str.toString());
   }      
}

输出：

string = geeks for geeks
After insertion = geeks fo41.35r geeks

长输入

// Java program to demonstrate StringBuffer insert
// for Long input.
import java.lang.*;
  
public class GFG 
{
    public static void main(String[] args)
    {
        StringBuffer str = new StringBuffer("geeks for geeks");
        System.out.println("string = " + str);
          
        // insert float value at offset 3
        str.insert(8, 546986L);
          
        // prints stringbuffer after insertion
        System.out.print("After insertion = ");
        System.out.println(str.toString());
   }      
}

输出：

string = geeks for geeks
After insertion = geeks fo546986r geeks

整数输入

// Java program to demonstrate StringBuffer insert
// for Int input.
import java.lang.*;
  
public class GFG 
{
    public static void main(String[] args)
    {
        StringBuffer str = 
            new StringBuffer("geeks for geeks");
        System.out.println("string = " + str);
          
        // insert float value at offset 8
        int x = 10;
        str.insert(8, x);
          
        // prints stringbuffer after insertion
        System.out.print("After insertion = ");
        System.out.println(str.toString());
   }      
}

输出：

string = geeks for geeks
After insertion = geeks fo10r geeks