📜  C#| BitConverter.ToChar()方法

📅  最后修改于: 2021-05-30 01:46:07             🧑  作者: Mango

此方法用于返回从字节数组中指定位置的两个字节转换而来的Unicode字符。

句法:

public static char ToChar (byte[] value, int startIndex);

参数:

返回值:该方法返回一个字符,该字符由从startIndex开始的两个字节组成。

例外情况:

下面的程序说明了BitConverter.ToChar(Byte [],Int32)方法的用法:

范例1:

// C# program to demonstrate
// BitConverter.ToChar(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
        for (int index = 1; index < bytes.Length - 1;
                                index = index + 2) {
  
            char values = BitConverter.ToChar(bytes, index);
            Console.WriteLine("index element   char");
            Console.WriteLine(" {0}     {1}     {2}",
                            index, bytes[index], 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     char
  1      0         
index  element     char
  3      42         *
index  element     char
  5      65         A
index  element     char
  7      125         }
index  element     char
  9      197         ?
index  element     char
  11      168         ?
index  element     char
  13      41         ?
index  element     char
  15      125         ?

示例2:对于ArgumentException

// C# program to demonstrate
// BitConverter.ToChar(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 };
  
        // Display the values of the myArr.
        Console.Write("Initial Array: ");
  
        // calling the PrintIndexAndValues()
        // method to print
        PrintIndexAndValues(bytes);
  
        // print char value
        for (int index = 1; index < bytes.Length; 
                            index = index + 2) {
  
            if (index == bytes.Length - 1) {
                Console.WriteLine();
                Console.WriteLine("startIndex equals the "+
                               "length of value minus 1.");
                char values = BitConverter.ToChar(bytes, index);
            }
            else {
                char values = BitConverter.ToChar(bytes, index);
                Console.WriteLine("index element     char");
                Console.WriteLine(" {0}     {1}      {2}", 
                                index, bytes[index], 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     char
  1      0         
index  element     char
  3      42         *
index  element     char
  5      65         A
index  element     char
  7      125         }
index  element     char
  9      197         ?
index  element     char
  11      168         ?
index  element     char
  13      41         ?

startIndex equals the length of value minus 1.
Exception Thrown: System.ArgumentException

示例3:对于ArgumentOutOfRangeException

// C# program to demonstrate
// BitConverter.ToChar(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 };
  
        // Display the values of the myArr.
        Console.Write("Initial Array: ");
  
        // calling the PrintIndexAndValues()
        // method to print
        PrintIndexAndValues(bytes);
  
        // print char value
        for (int index = 0; index < bytes.Length + 1; 
                                 index = index + 2) {
  
            if (index == bytes.Length) {
                Console.WriteLine();
                Console.WriteLine("startIndex is greater than "+
                                "the length of value minus 1.");
                char values = BitConverter.ToChar(bytes, index);
            }
            else {
                char values = BitConverter.ToChar(bytes, index);
                Console.WriteLine("index element     char");
                Console.WriteLine(" {0}     {1}      {2}", 
                                index, bytes[index], 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     char
  0      32          
index  element     char
  2      0         ?
index  element     char
  4      0         ?
index  element     char
  6      0         ?
index  element     char
  8      0         ?
index  element     char
  10      0         ?
index  element     char
  12      3         ?
index  element     char
  14      4         ?

startIndex is greater than the length of value minus 1.
Exception Thrown: System.ArgumentOutOfRangeException

示例4:对于ArgumentNullException

// C# program to demonstrate
// BitConverter.ToChar(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 char value
  
            char values = BitConverter.ToChar(bytes, 0);
        }
        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/zh-cn/dotnet/api/system.bitconverter.tochar?view=netframework-4.7.2