C# BitConverter.ToUInt64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位无符号整数。

用法:

public static ulong ToUInt64 (byte[] value, int startIndex);

参数：

value:它是一个字节数组。
startIndex:它是值内的起始位置。

返回值：此方法返回一个由startIndex开始的八个字节组成的64位无符号整数。

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.ToUInt64方法的用法：

示例1:

// C# program to demonstrate 
// BitConverter.ToUInt64(Byte[], Int32); 
// Method 
using System; 
  
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"+ 
                          "             ulong value"); 
          
        for (int index = 0; index < bytes.Length - 7; 
                                index = index + 8) { 
  
            ulong values = BitConverter.ToUInt64(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             ulong 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.ToUInt64(Byte[], Int32); 
// Method 
using System; 
   
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           element"+ 
                    "                 ulong 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); 
  
                ulong values = BitConverter.ToUInt64(bytes, index); 
                  
                Console.WriteLine("  {0}      {1}      {2}", index, 
                   BitConverter.ToString(bytes, index, 8), values); 
            } 
  
            else { 
                ulong values = BitConverter.ToUInt64(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 32 

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

index           element                 ulong value
  0      20-00-00-2A-00-41-00-7D      9007270723701440544
  8      00-C5-00-A8-03-29-04-7D      9008370250328098048
Exception Thrown: System.ArgumentException

示例3:对于ArgumentNullException

// C# program to demonstrate 
// BitConverter.ToUInt64(Byte[], Int32); 
// Method 
using System; 
  
class GFG { 
  
    // Main Method 
    public static void Main() 
    { 
  
        try { 
  
            // Define an array of byte values. 
            byte[] bytes = null; 
  
            // get the long value 
  
            ulong values = BitConverter.ToUInt64(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.touint64?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.ToUInt64 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。