C＃| Buffer.BlockCopy(Array，Int32，Array，Int32，Int32)方法

此方法用于将指定数量的字节从以特定偏移量开始的源数组复制到以特定偏移量开始的目标数组。

句法：

public static void BlockCopy (Array src, int srcOffset, Array dst, int dstOffset, int count);

参数：

src: It is the source buffer.

srcOffset: It is the zero-based byte offset into src.

dst: It is the destination buffer.

dstOffset: The zero-based byte offset into dst.

count: The number of bytes to copy.

例外情况：

• ArgumentNullException：如果src或dst为null。
• ArgumentException：如果src或dst不是原始数组，或者src中的字节数小于srcOffset加上count 。或dst中的字节数小于dstOffset加上count 。
• ArgumentOutOfRangeException：如果srcOffset ， dstOffset或count小于0。

下面的程序说明了Buffer.BlockCopy(Array，Int32，Array，Int32，Int32)方法的使用：

范例1：

// C# program to demonstrate
// Buffer.BlockCopy(Array, Int32,
// Array, Int32, Int32) Method
using System;
  
class GFG {
  
// Main Method
public static void Main()
{
  
    try {
  
        // Declaring src and dest array
        long[] src = {15, 16, 17, 18 };
        long[] dest = {17, 18, 19, 20 };
  
        Console.WriteLine("Initial Array values:");
        Console.WriteLine();
          
        // Display hexadecimal values
        Console.WriteLine("Array element in hexadecimal form:");
        displayhexvalue(src, "src");
        displayhexvalue(dest, "dest");
          
        // display Individual byte
        Console.WriteLine("Individual bytes:");
        displaybytes(src, "src");
        displaybytes(dest, "dest");
  
        // copying the specified number of bytes
        // using Buffer.BlockCopy() method
        Buffer.BlockCopy(src, 4, dest, 7, 6);
  
        Console.WriteLine();
        Console.WriteLine("Array after operation:");
        Console.WriteLine();
          
        // display hexadecimal values
        Console.WriteLine("Array element in hexadecimal form:");
        displayhexvalue(src, "src");
        displayhexvalue(dest, "dest");
          
        // display hexadecimal value
        Console.WriteLine("Individual bytes:");
        displaybytes(src, "src");
        displaybytes(dest, "dest");
    }
    catch (ArgumentNullException e) {
  
        Console.Write("Exception Thrown: ");
        Console.Write("{0}", e.GetType(), e.Message);
    }
    catch (ArgumentOutOfRangeException e) {
  
        Console.Write("Exception Thrown: ");
        Console.Write("{0}", e.GetType(), e.Message);
    }
    catch (ArgumentException e) {
  
        Console.Write("Exception Thrown: ");
        Console.Write("{0}", e.GetType(), e.Message);
    }
}
  
// Display the individual 
// array element values 
// in hexadecimal.
public static void displayhexvalue(Array a, 
                              string name)
{
    // print the name
    Console.Write("{0, 5}:", name);
  
    // Display value one by one
    for (int i = 0; i < a.Length; i++)
        Console.Write(" {0:X16} ", a.GetValue(i));
  
    Console.WriteLine();
}
  
// Display the individual 
// bytes in the array
// in hexadecimal.
public static void displaybytes(Array arr, 
                              string name)
{
    // print the name
    Console.Write("{0, 5}:", name);
  
    // loop to traverse 
    // every element of the array
    for (int i = 0; i < arr.Length; i++) {
          
        // gettig byte array
        // converted from long array
        byte[] bytes = BitConverter.GetBytes((long)arr.GetValue(i));
  
        // display each byte value
        foreach(byte byteValue in bytes)
            Console.Write(" {0:X2}", byteValue);
    }
    Console.WriteLine();
}
}

输出：

Initial Array values:

Array element in hexadecimal form:
src: 000000000000000F 0000000000000010 0000000000000011 0000000000000012
dest: 0000000000000011 0000000000000012 0000000000000013 0000000000000014
Individual bytes:
src: 0F 00 00 00 00 00 00 00 10 00 00 00 00 00 00 00 11 00 00 00 00 00 00 00 12 00 00 00 00 00 00 00
dest: 11 00 00 00 00 00 00 00 12 00 00 00 00 00 00 00 13 00 00 00 00 00 00 00 14 00 00 00 00 00 00 00

Array after operation:

Array element in hexadecimal form:
src: 000000000000000F 0000000000000010 0000000000000011 0000000000000012
dest: 0000000000000011 0000000010000000 0000000000000013 0000000000000014
Individual bytes:
src: 0F 00 00 00 00 00 00 00 10 00 00 00 00 00 00 00 11 00 00 00 00 00 00 00 12 00 00 00 00 00 00 00
dest: 11 00 00 00 00 00 00 00 00 00 00 10 00 00 00 00 13 00 00 00 00 00 00 00 14 00 00 00 00 00 00 00

示例2：对于ArgumentNullException

// C# program to demonstrate
// Buffer.BlockCopy(Array, Int32,
// Array, Int32, Int32) Method
using System;
  
class GFG {
  
// Main Method
public static void Main()
{
  
    try {
  
        // Declaring src and dest array
        long[] src = {15, 16, 17, 18};
        long[] dest = {17, 18, 19, 20};
  
        Console.WriteLine("Initial Array values:");
        Console.WriteLine();
          
        // Display hexadecimal values
        Console.WriteLine("Array element in hexadecimal form:");
        displayhexvalue(src, "src");
        displayhexvalue(dest, "dest");
          
        // display Individual byte
        Console.WriteLine("Individual bytes:");
        displaybytes(src, "src");
        displaybytes(dest, "dest");
  
        // copying the specified number of bytes
        // using Buffer.BlockCopy() method
        Console.WriteLine("src and dst are null:");
        Buffer.BlockCopy(null, 4, null, 7, 6);
  
        Console.WriteLine();
        Console.WriteLine("Array after operation:");
        Console.WriteLine();
          
        // display hexadecimal values
        Console.WriteLine("Array element in hexadecimal form:");
        displayhexvalue(src, "src");
        displayhexvalue(dest, "dest");
          
        // display hexadecimal value
        Console.WriteLine("Individual bytes:");
        displaybytes(src, "src");
        displaybytes(dest, "dest");
    }
    catch (ArgumentNullException e) {
  
        Console.Write("Exception Thrown: ");
        Console.Write("{0}", e.GetType(), e.Message);
    }
    catch (ArgumentOutOfRangeException e) {
  
        Console.Write("Exception Thrown: ");
        Console.Write("{0}", e.GetType(), e.Message);
    }
    catch (ArgumentException e) {
  
        Console.Write("Exception Thrown: ");
        Console.Write("{0}", e.GetType(), e.Message);
    }
}
  
// Display the individual array
// element values in hexadecimal.
public static void displayhexvalue(Array a,
                              string name)
{
    // print the name
    Console.Write("{0, 5}:", name);
  
    // Display value one by one
    for (int i = 0; i < a.Length; i++)
        Console.Write(" {0:X16} ", a.GetValue(i));
  
    Console.WriteLine();
}
  
// Display the individual bytes
// in the array in hexadecimal.
public static void displaybytes(Array arr, 
                              string name)
{
      
    // print the name
    Console.Write("{0, 5}:", name);
  
    // loop to traverse every
    // element of the array
    for (int i = 0; i < arr.Length; i++) {
          
        // gettig byte array converted
        // from long array
        byte[] bytes = BitConverter.GetBytes((long)arr.GetValue(i));
  
        // display each byte value
        foreach(byte byteValue in bytes)
            Console.Write(" {0:X2}", byteValue);
    }
    Console.WriteLine();
}
}

输出：

Initial Array values:

Array element in hexadecimal form:
src: 000000000000000F 0000000000000010 0000000000000011 0000000000000012
dest: 0000000000000011 0000000000000012 0000000000000013 0000000000000014
Individual bytes:
src: 0F 00 00 00 00 00 00 00 10 00 00 00 00 00 00 00 11 00 00 00 00 00 00 00 12 00 00 00 00 00 00 00
dest: 11 00 00 00 00 00 00 00 12 00 00 00 00 00 00 00 13 00 00 00 00 00 00 00 14 00 00 00 00 00 00 00
src and dst are null:
Exception Thrown: System.ArgumentNullException

示例3：对于ArgumentOutOfRangeException

// C# program to demonstrate
// Buffer.BlockCopy(Array, Int32, 
// Array, Int32, Int32) Method
using System;
  
class GFG {
  
// Main Method
public static void Main()
{
  
    try {
  
        // Declaring src and dest array
        long[] src = {15, 16, 17, 18};
        long[] dest = {17, 18, 19, 20};
  
        Console.WriteLine("Initial Array values:");
        Console.WriteLine();
          
        // Display hexadecimal values
        Console.WriteLine("Array element in hexadecimal form:");
        displayhexvalue(src, "src");
        displayhexvalue(dest, "dest");
          
        // display Individual byte
        Console.WriteLine("Individual bytes:");
        displaybytes(src, "src");
        displaybytes(dest, "dest");
  
        // copying the specified number of bytes
        // using Buffer.BlockCopy() method
        Console.WriteLine("srcoffest and destoffset are less than zero:");
        Buffer.BlockCopy(src, -4, dest, -7, 6);
  
        Console.WriteLine();
        Console.WriteLine("Array after operation:");
        Console.WriteLine();
          
        // display hexadecimal values
        Console.WriteLine("Array element in hexadecimal form:");
        displayhexvalue(src, "src");
        displayhexvalue(dest, "dest");
          
        // display hexadecimal value
        Console.WriteLine("Individual bytes:");
        displaybytes(src, "src");
        displaybytes(dest, "dest");
    }
    catch (ArgumentNullException e) {
  
        Console.Write("Exception Thrown: ");
        Console.Write("{0}", e.GetType(), e.Message);
    }
    catch (ArgumentOutOfRangeException e) {
  
        Console.Write("Exception Thrown: ");
        Console.Write("{0}", e.GetType(), e.Message);
    }
    catch (ArgumentException e) {
  
        Console.Write("Exception Thrown: ");
        Console.Write("{0}", e.GetType(), e.Message);
    }
}
  
// Display the individual array
// element values in hexadecimal.
public static void displayhexvalue(Array a, 
                              string name)
{
    // print the name
    Console.Write("{0, 5}:", name);
  
    // Display value one by one
    for (int i = 0; i < a.Length; i++)
        Console.Write(" {0:X16} ", a.GetValue(i));
  
    Console.WriteLine();
}
  
// Display the individual bytes
// in the array in hexadecimal.
public static void displaybytes(Array arr, 
                             string name)
{
    // print the name
    Console.Write("{0, 5}:", name);
  
    // loop to traverse every
    // element of the array
    for (int i = 0; i < arr.Length; i++) {
          
        // gettig byte array converted
        // from long array
        byte[] bytes = BitConverter.GetBytes((long)arr.GetValue(i));
  
        // display each byte value
        foreach(byte byteValue in bytes)
            Console.Write(" {0:X2}", byteValue);
    }
    Console.WriteLine();
}
}

输出：

Initial Array values:

Array element in hexadecimal form:
src: 000000000000000F 0000000000000010 0000000000000011 0000000000000012
dest: 0000000000000011 0000000000000012 0000000000000013 0000000000000014
Individual bytes:
src: 0F 00 00 00 00 00 00 00 10 00 00 00 00 00 00 00 11 00 00 00 00 00 00 00 12 00 00 00 00 00 00 00
dest: 11 00 00 00 00 00 00 00 12 00 00 00 00 00 00 00 13 00 00 00 00 00 00 00 14 00 00 00 00 00 00 00
srcoffest and destoffset are less than zero:
Exception Thrown: System.ArgumentOutOfRangeException

示例4：对于ArgumentException

// C# program to demonstrate
// Buffer.BlockCopy(Array, Int32,
// Array, Int32, Int32)
// Method
using System;
  
class GFG {
  
// Main Method
public static void Main()
{
  
    try {
  
        // Declaring src and dest array
        long[] src = {15, 16, 17, 18};
        long[] dest = {17, 18, 19, 20};
  
        Console.WriteLine("Initial Array values:");
        Console.WriteLine();
          
        // Display hexadecimal values
        Console.WriteLine("Array element in hexadecimal form:");
        displayhexvalue(src, "src");
        displayhexvalue(dest, "dest");
          
        // display Individual byte
        Console.WriteLine("Individual bytes:");
        displaybytes(src, "src");
        displaybytes(dest, "dest");
  
        // copying the specified number of bytes
        // using Buffer.BlockCopy() method
        Console.WriteLine("srcoffest and destoffset are less than zero:");
        Buffer.BlockCopy(src, 4, dest, 7, 70);
  
        Console.WriteLine();
        Console.WriteLine("Array after operation:");
        Console.WriteLine();
          
        // display hexadecimal values
        Console.WriteLine("Array element in hexadecimal form:");
        displayhexvalue(src, "src");
        displayhexvalue(dest, "dest");
          
        // display hexadecimal value
        Console.WriteLine("Individual bytes:");
        displaybytes(src, "src");
        displaybytes(dest, "dest");
    }
    catch (ArgumentNullException e) {
  
        Console.Write("Exception Thrown: ");
        Console.Write("{0}", e.GetType(), e.Message);
    }
    catch (ArgumentOutOfRangeException e) {
  
        Console.Write("Exception Thrown: ");
        Console.Write("{0}", e.GetType(), e.Message);
    }
    catch (ArgumentException e) {
  
        Console.Write("Exception Thrown: ");
        Console.Write("{0}", e.GetType(), e.Message);
    }
}
  
// Display the individual array
// element values in hexadecimal.
public static void displayhexvalue(Array a,
                               string name)
{
    // print the name
    Console.Write("{0, 5}:", name);
  
    // Display value one by one
    for (int i = 0; i < a.Length; i++)
        Console.Write(" {0:X16} ", a.GetValue(i));
  
    Console.WriteLine();
}
  
// Display the individual bytes
// in the array in hexadecimal.
public static void displaybytes(Array arr, 
                              string name)
{
    // print the name
    Console.Write("{0, 5}:", name);
  
    // loop to traverse every
    // element of the array
    for (int i = 0; i < arr.Length; i++) {
          
        // getting byte array 
        // converted from long array
        byte[] bytes = BitConverter.GetBytes((long)arr.GetValue(i));
  
        // display each byte value
        foreach(byte byteValue in bytes)
            Console.Write(" {0:X2}", byteValue);
    }
    Console.WriteLine();
}
}

输出：

Initial Array values:

Array element in hexadecimal form:
src: 000000000000000F 0000000000000010 0000000000000011 0000000000000012
dest: 0000000000000011 0000000000000012 0000000000000013 0000000000000014
Individual bytes:
src: 0F 00 00 00 00 00 00 00 10 00 00 00 00 00 00 00 11 00 00 00 00 00 00 00 12 00 00 00 00 00 00 00
dest: 11 00 00 00 00 00 00 00 12 00 00 00 00 00 00 00 13 00 00 00 00 00 00 00 14 00 00 00 00 00 00 00
srcoffest and destoffset are less than zero:
Exception Thrown: System.ArgumentException

参考：

• https://docs.microsoft.com/zh-cn/dotnet/api/system.buffer.blockcopy?view=netframework-4.7.2