Windows apps
Collapse the table of content
Expand the table of content
Information
The topic you requested is included in another documentation set. For convenience, it's displayed below. Choose Switch to see the topic in its original location.

BitConverter.ToInt32 Method (Byte[], Int32)

 
System_CAPS_noteNote

The .NET API Reference documentation has a new home. Visit the .NET API Browser on docs.microsoft.com to see the new experience.

Returns a 32-bit signed integer converted from four bytes at a specified position in a byte array.

Namespace:   System
Assembly:  mscorlib (in mscorlib.dll)

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

Parameters

value
Type: System.Byte[]

An array of bytes.

startIndex
Type: System.Int32

The starting position within value.

Return Value

Type: System.Int32

A 32-bit signed integer formed by four bytes beginning at startIndex.

Exception Condition
ArgumentException

startIndex is greater than or equal to the length of value minus 3, and is less than or equal to the length of value minus 1.

ArgumentNullException

value is null.

ArgumentOutOfRangeException

startIndex is less than zero or greater than the length of value minus 1.

The ToInt32 method converts the bytes from index startIndex to startIndex + 3 to an Int32 value. The order of bytes in the array must reflect the endianness of the computer system's architecture; for more information, see the Remarks section of BitConverter.

The following example uses the ToInt32 method to create Int32 values from a four-byte array and from the upper four bytes of an eight-byte array. It also uses the GetBytes(Int32) and ToInt32 methods to round-trip an Int32 value.

using System;

public class Example
{
   public static void Main()
   {
      // Create an Integer from a 4-byte array.
      Byte[] bytes1 = { 0xEC, 0x00, 0x00, 0x00 };
      Console.WriteLine("{0}--> 0x{1:X4} ({1:N0})", FormatBytes(bytes1),
                                      BitConverter.ToInt32(bytes1, 0));
      // Create an Integer from the upper four bytes of a byte array.
      Byte[] bytes2 = BitConverter.GetBytes(Int64.MaxValue / 2);
      Console.WriteLine("{0}--> 0x{1:X4} ({1:N0})", FormatBytes(bytes2),
                                      BitConverter.ToInt32(bytes2, 4));

      // Round-trip an integer value.
      int original = (int) Math.Pow(16, 3);
      Byte[] bytes3 = BitConverter.GetBytes(original);
      int restored = BitConverter.ToInt32(bytes3, 0);
      Console.WriteLine("0x{0:X4} ({0:N0}) --> {1} --> 0x{2:X4} ({2:N0})", original, 
                        FormatBytes(bytes3), restored);
   }

   private static string FormatBytes(Byte[] bytes)
   {
       string value = "";
       foreach (var byt in bytes)
          value += String.Format("{0:X2} ", byt);

       return value;
   }
}
// The example displays the following output:
//       EC 00 00 00 --> 0x00EC (236)
//       FF FF FF FF FF FF FF 3F --> 0x3FFFFFFF (1,073,741,823)
//       0x1000 (4,096) --> 00 10 00 00  --> 0x1000 (4,096)

Universal Windows Platform
Available since 8
.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Silverlight
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
Return to top
Show:
© 2017 Microsoft