C# BitConverter.ToInt64()用法及代码示例

此方法用于返回从字节数组中指定位置的八个字节转换而来的64位有符号整数。

用法:

public static long ToInt64 (byte[] value, int startIndex);

参数：

value:它是一个字节数组。
startIndex:它是值中的起始位置。

返回值：此方法返回一个由两个字节组成的64位带符号整数，该整数从startIndex开始。

异常：

ArgumentException：如果startIndex大于或等于值的长度减去7，并且小于或等于值的长度减去1。
ArgumentNullException：如果值为空。
ArgumentOutOfRangeException：如果startIndex小于零或大于值的长度减1。

以下示例程序旨在说明BitConverter.ToInt64(Byte []，Int32)方法的用法：

示例1:

// C# program to demonstrate 
// BitConverter.ToInt64(Byte[], Int32); 
// Method 
using System; 
  
public class GFG { 
  
    // Main Method 
    public static void Main() 
    { 
  
        try { 
  
            // Define an array of byte values. 
            byte[] bytes = {32, 0, 0, 42, 0,  
                            65, 0, 125, 0, 197,  
                            0, 168, 3, 41, 4,  
                                     125, 32}; 
  
            // Display the values of the myArr. 
            Console.Write("Initial Array: "); 
  
            // calling the PrintIndexAndValues() 
            // method to print 
            PrintIndexAndValues(bytes); 
  
            // print char value 
            Console.WriteLine("index       byte Array"+                     
             "                            long value"); 
              
            for (int index = 0; index < bytes.Length - 7; 
                                     index = index + 8) { 
  
                long values = BitConverter.ToInt64(bytes, index); 
  
                Console.WriteLine(" {0}     {1}         {2}", 
                       index, BitConverter.ToString(bytes, 
                                       index, 8), values); 
            } 
        } 
        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); 
        } 
    } 
  
    // Defining the method 
    // PrintIndexAndValues 
    public static void PrintIndexAndValues(byte[] myArr) 
    { 
        for (int i = 0; i < myArr.Length; i++) { 
  
            Console.Write("{0} ", myArr[i]); 
        } 
  
        Console.WriteLine(); 
        Console.WriteLine(); 
    } 
}

输出：

Initial Array: 32 0 0 42 0 65 0 125 0 197 0 168 3 41 4 125 32 

index       byte Array                            long value
 0     20-00-00-2A-00-41-00-7D         9007270723701440544
 8     00-C5-00-A8-03-29-04-7D         9008370250328098048

示例2:对于ArgumentException

// C# program to demonstrate 
// BitConverter.ToInt64(Byte[], Int32); 
// Method 
using System; 
  
public class GFG { 
  
    // Main Method 
    public static void Main() 
    { 
  
        try { 
  
            // Define an array of byte values. 
        byte[] bytes = {32, 0, 0, 42, 0, 65,  
                        0, 125, 0, 197, 0,  
                        168, 3, 41, 4, 125}; 
  
            // Display the values of the myArr. 
            Console.Write("Initial Array: "); 
  
            // calling the PrintIndexAndValues() 
            // method to print 
            PrintIndexAndValues(bytes); 
  
            // print char value 
            Console.WriteLine("index       element"+                     
             "                        float value"); 
               
            for (int index = 1; index < bytes.Length - 6; 
                                     index = index + 8) { 
  
                if (index == bytes.Length - 7) { 
  
                    Console.WriteLine(); 
                    Console.WriteLine("startindex is {0} which is equals"+ 
                               " to the length of Array minus 7.", index); 
                                 
                    long values = BitConverter.ToInt64(bytes, index); 
                      
                    Console.WriteLine(" {0}     {1}         {2}", index, 
                                         BitConverter.ToString(bytes,  
                                                  index, 8), values); 
                } 
                else { 
                    long values = BitConverter.ToInt64(bytes, index); 
                    Console.WriteLine(" {0}     {1}         {2}", 
                           index, BitConverter.ToString(bytes,  
                                           index, 8), values); 
                } 
            } 
        } 
        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); 
        } 
    } 
  
    // Defining the method 
    // PrintIndexAndValues 
    public static void PrintIndexAndValues(byte[] myArr) 
    { 
        for (int i = 0; i < myArr.Length; i++) { 
  
            Console.Write("{0} ", myArr[i]); 
        } 
  
        Console.WriteLine(); 
        Console.WriteLine(); 
        Console.WriteLine("intial Array in string: {0} ",  
                           BitConverter.ToString(myArr)); 
        Console.WriteLine(); 
    } 
}

输出：

Initial Array: 32 0 0 42 0 65 0 125 0 197 0 168 3 41 4 125 

intial Array in string: 20-00-00-2A-00-41-00-7D-00-C5-00-A8-03-29-04-7D 

index       element                        float value
 1     00-00-2A-00-41-00-7D-00         35184651264458752

startindex is 9 which is equals to the length of Array minus 7.
Exception Thrown: System.ArgumentException

示例3:对于ArgumentOutOfRangeException

// C# program to demonstrate 
// BitConverter.ToInt64(Byte[], Int32); 
// Method 
using System; 
  
public class GFG { 
  
    // Main Method 
    public static void Main() 
    { 
  
        try { 
  
            // Define an array of byte values. 
            byte[] bytes = {32, 0, 0, 42, 0, 65, 
                            0, 125, 0, 197, 0,  
                            168, 3, 41, 4, 125}; 
  
            // Display the values of the myArr. 
            Console.Write("Initial Array: "); 
  
            // calling the PrintIndexAndValues() 
            // method to print 
            PrintIndexAndValues(bytes); 
  
            // print char value 
            Console.WriteLine("index         element"+ 
                     "                  float value"); 
                       
            for (int index = 0; index < bytes.Length + 1; 
                                    index = index + 8) { 
  
                if (index == bytes.Length) { 
  
                    Console.WriteLine(); 
                    Console.WriteLine("startindex is {0} which is greater"+ 
                               " than the Length of array minus 1", index); 
                                 
                    long values = BitConverter.ToInt64(bytes, index); 
                      
                    Console.WriteLine(" {0}     {1}         {2}", index,  
                                         BitConverter.ToString(bytes,  
                                                  index, 8), values); 
                } 
                else { 
                    long values = BitConverter.ToInt64(bytes, index); 
                    Console.WriteLine(" {0}     {1}         {2}",  
                           index, BitConverter.ToString(bytes,  
                                           index, 8), values); 
                } 
            } 
        } 
        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); 
        } 
    } 
  
    // Defining the method 
    // PrintIndexAndValues 
    public static void PrintIndexAndValues(byte[] myArr) 
    { 
        for (int i = 0; i < myArr.Length; i++) { 
  
            Console.Write("{0} ", myArr[i]); 
        } 
  
        Console.WriteLine(); 
        Console.WriteLine(); 
        Console.WriteLine("Intial Array in string: {0} ",  
                           BitConverter.ToString(myArr)); 
        Console.WriteLine(); 
    } 
}

输出：

Initial Array: 32 0 0 42 0 65 0 125 0 197 0 168 3 41 4 125 

Intial Array in string: 20-00-00-2A-00-41-00-7D-00-C5-00-A8-03-29-04-7D 

index         element                  float value
 0     20-00-00-2A-00-41-00-7D         9007270723701440544
 8     00-C5-00-A8-03-29-04-7D         9008370250328098048

startindex is 16 which is greater than the Length of array minus 1
Exception Thrown: System.ArgumentOutOfRangeException

示例4:对于ArgumentNullException

// C# program to demonstrate 
// BitConverter.ToInt64(Byte[], Int32); 
// Method 
using System; 
  
public class GFG { 
  
    // Main Method 
    public static void Main() 
    { 
  
        try { 
  
            // Define an array of byte values. 
            byte[] bytes = null; 
  
            // get the long value 
  
            long values = BitConverter.ToInt64(bytes, 0); 
            Console.Write("{0}", values); 
        } 
        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); 
        } 
    } 
}

输出：

Exception Thrown: System.ArgumentNullException

参考：

https://docs.microsoft.com/en-us/dotnet/api/system.bitconverter.toint64?view=netframework-4.7.2

相关用法

注：本文由纯净天空筛选整理自RohitPrasad3大神的英文原创作品 C# | BitConverter.ToInt64() Method。非经特殊声明，原始代码版权归原作者所有，本译文未经允许或授权，请勿转载或复制。