共用方式為


BitConverter.ToUInt32 Method

Microsoft Silverlight will reach end of support after October 2021. Learn more.

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

This API is not CLS-compliant. 

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

Syntax

'Declaration
<CLSCompliantAttribute(False)> _
Public Shared Function ToUInt32 ( _
    value As Byte(), _
    startIndex As Integer _
) As UInteger
[CLSCompliantAttribute(false)]
public static uint ToUInt32(
    byte[] value,
    int startIndex
)

Parameters

  • startIndex
    Type: System.Int32
    The starting position within value.

Return Value

Type: System.UInt32
A 32-bit unsigned integer formed by four bytes beginning at startIndex.

Exceptions

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 nulla null reference (Nothing in Visual Basic).

ArgumentOutOfRangeException

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

Examples

The following code example converts elements of Byte arrays to UInt32 values with the ToUInt32 method.

' Example of the BitConverter.ToUInt32 method.

Module Example

   Const formatter As String = "{0,5}{1,17}{2,15}"

   ' Convert four Byte array elements to a UInt32 and display it.
   Sub BAToUInt32(ByVal outputBlock As System.Windows.Controls.TextBlock, ByVal bytes() As Byte, ByVal index As Integer)

      Dim value As UInt32 = BitConverter.ToUInt32(bytes, index)

      outputBlock.Text &= String.Format(formatter, index, _
          BitConverter.ToString(bytes, index, 4), value) & vbCrLf
   End Sub

   Public Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)
      Dim byteArray As Byte() = { _
           15, 0, 0, 0, 0, 16, 0, 255, 3, 0, _
            0, 202, 154, 59, 255, 255, 255, 255, 127}

      outputBlock.Text &= String.Format( _
          "This example of the BitConverter.ToUInt32( Byte( ), " & _
          "Integer ) " & vbCrLf & "method generates the " & _
          "following output. It converts elements " & vbCrLf & _
          "of a Byte array to UInt32 values." & vbCrLf) & vbCrLf
      outputBlock.Text &= "initial Byte array" & vbCrLf
      outputBlock.Text &= "------------------" & vbCrLf
      outputBlock.Text &= BitConverter.ToString(byteArray) & vbCrLf
      outputBlock.Text &= vbCrLf
      outputBlock.Text &= String.Format(formatter, "index", "array elements", _
          "UInt32") & vbCrLf
      outputBlock.Text &= String.Format(formatter, "-----", "--------------", _
          "------") & vbCrLf

      ' Convert Byte array elements to UInt32 values.
      BAToUInt32(outputBlock, byteArray, 1)
      BAToUInt32(outputBlock, byteArray, 0)
      BAToUInt32(outputBlock, byteArray, 7)
      BAToUInt32(outputBlock, byteArray, 3)
      BAToUInt32(outputBlock, byteArray, 10)
      BAToUInt32(outputBlock, byteArray, 15)
      BAToUInt32(outputBlock, byteArray, 14)
   End Sub
End Module

' This example of the BitConverter.ToUInt32( Byte( ), Integer )
' method generates the following output. It converts elements
' of a Byte array to UInt32 values.
' 
' initial Byte array
' ------------------
' 0F-00-00-00-00-10-00-FF-03-00-00-CA-9A-3B-FF-FF-FF-FF-7F
' 
' index   array elements         UInt32
' -----   --------------         ------
'     1      00-00-00-00              0
'     0      0F-00-00-00             15
'     7      FF-03-00-00           1023
'     3      00-00-10-00        1048576
'    10      00-CA-9A-3B     1000000000
'    15      FF-FF-FF-7F     2147483647
'    14      FF-FF-FF-FF     4294967295
// Example of the BitConverter.ToUInt32 method.
using System;

class Example
{
   const string formatter = "{0,5}{1,17}{2,15}";

   // Convert four byte array elements to a uint and display it.
   public static void BAToUInt32(System.Windows.Controls.TextBlock outputBlock, byte[] bytes, int index)
   {
      uint value = BitConverter.ToUInt32(bytes, index);

      outputBlock.Text += String.Format(formatter, index,
          BitConverter.ToString(bytes, index, 4), value) + "\n";
   }

   public static void Demo(System.Windows.Controls.TextBlock outputBlock)
   {
      byte[] byteArray = {
             15,   0,   0,   0,   0,  16,   0, 255,   3,   0, 
              0, 202, 154,  59, 255, 255, 255, 255, 127 };

      outputBlock.Text += String.Format(
          "This example of the BitConverter.ToUInt32( byte[ ], " +
          "int ) \nmethod generates the following output. It " +
          "converts elements \nof a byte array to uint values.\n") + "\n";
      outputBlock.Text += "initial byte array" + "\n";
      outputBlock.Text += "------------------" + "\n";
      outputBlock.Text += BitConverter.ToString(byteArray) + "\n";
      outputBlock.Text += "\n";
      outputBlock.Text += String.Format(formatter, "index", "array elements",
          "uint") + "\n";
      outputBlock.Text += String.Format(formatter, "-----", "--------------",
          "----") + "\n";

      // Convert byte array elements to uint values.
      BAToUInt32(outputBlock, byteArray, 1);
      BAToUInt32(outputBlock, byteArray, 0);
      BAToUInt32(outputBlock, byteArray, 7);
      BAToUInt32(outputBlock, byteArray, 3);
      BAToUInt32(outputBlock, byteArray, 10);
      BAToUInt32(outputBlock, byteArray, 15);
      BAToUInt32(outputBlock, byteArray, 14);
   }
}

/*
This example of the BitConverter.ToUInt32( byte[ ], int )
method generates the following output. It converts elements
of a byte array to uint values.

initial byte array
------------------
0F-00-00-00-00-10-00-FF-03-00-00-CA-9A-3B-FF-FF-FF-FF-7F

index   array elements           uint
-----   --------------           ----
    1      00-00-00-00              0
    0      0F-00-00-00             15
    7      FF-03-00-00           1023
    3      00-00-10-00        1048576
   10      00-CA-9A-3B     1000000000
   15      FF-FF-FF-7F     2147483647
   14      FF-FF-FF-FF     4294967295
*/

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.