📜  C#| BitConverter.ToInt32()方法

📅  最后修改于: 2021-05-29 21:36:24             🧑  作者: Mango

BitConverter.ToInt32(Byte [],Int32)方法用于返回一个32位有符号整数,该整数是从字节数组中指定位置的四个字节转换而来的。

句法:

public static int ToInt32 (byte[] value, int startIndex);

参数:

返回值:该方法返回一个32位带符号整数,该整数由从startIndex开始的两个字节组成。

例外情况:

  • ArgumentException:如果startIndex大于或等于值的长度减去3,并且小于或等于值的长度减去1。
  • ArgumentNullException:如果该值为null。
  • ArgumentOutOfRangeException:如果startIndex小于零或大于值的长度减去1。

下面的程序说明了BitConverter.ToInt32(Byte [],Int32)方法的用法:

范例1:

// C# program to demonstrate
// BitConverter.ToInt32(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           int value");
        for (int index = 0; index < bytes.Length - 3;
                              index = index + 4) {
  
            int values = BitConverter.ToInt16(bytes, index);
  
            Console.WriteLine(" {0}     {1}         {2}",
             index, BitConverter.ToString(bytes, index,
                                           4), 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       int value
  0        20-00-00-2A         32
  4        00-41-00-7D         16640
  8        00-C5-00-A8         -15104
  12        03-29-04-7D         10499

示例2:对于ArgumentException

// C# program to demonstrate
// BitConverter.ToInt32(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
        Console.WriteLine("index      element          int value");
        for (int index = 1; index < bytes.Length - 2;
                                 index = index + 4) {
  
            if (index == bytes.Length - 3) {
                Console.WriteLine();
                Console.WriteLine("startIndex equals the "+
                               "length of value minus 3.");
                int values = BitConverter.ToInt32(bytes, index);
                Console.WriteLine("  {0}      {1}         {2}",
                 index, BitConverter.ToString(bytes, index, 4), values);
            }
            else {
                int values = BitConverter.ToInt32(bytes, index);
                Console.WriteLine("  {0}      {1}         {2}",
                 index, BitConverter.ToString(bytes, index, 4), 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          int value
  1      00-00-2A-00         2752512
  5      41-00-7D-00         8192065
  9      C5-00-A8-03         61341893

startIndex equals the length of value minus 3.
Exception Thrown: System.ArgumentException

示例3:对于ArgumentOutOfRangeException

// C# program to demonstrate
// BitConverter.ToInt32(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
        Console.WriteLine("index      element          int value");
          
        for (int index = 0; index < bytes.Length + 1; 
                                index = index + 4) {
  
            if (index == bytes.Length) {
                Console.WriteLine();
                Console.WriteLine("startIndex is greater than "+
                                 "the length of value minus 1");
                int values = BitConverter.ToInt32(bytes, index);
                Console.WriteLine("  {0}      {1}         {2}",
                 index, BitConverter.ToString(bytes, index, 4), values);
            }
            else {
                int values = BitConverter.ToInt32(bytes, index);
                Console.WriteLine("  {0}      {1}         {2}",
                 index, BitConverter.ToString(bytes, index, 4), 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          int value
  0      20-00-00-2A         704643104
  4      00-41-00-7D         2097168640
  8      00-C5-00-A8         -1476344576
  12      03-29-04-7D         2097424643

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.ToInt32(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 int value
  
        int values = BitConverter.ToInt32(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/zh-cn/dotnet/api/system.bitconverter.toint32?view=netframework-4.7.2