Marshal.WriteByte 方法

定义

命名空间:

System.Runtime.InteropServices

程序集:

System.Runtime.InteropServices.dll

将单个字节值写入到非托管内存。

重载

WriteByte(Object, Int32, Byte)	已过时. 按指定偏移量将单字节值写入非托管内存。
WriteByte(IntPtr, Byte)	将单个字节值写入到非托管内存。
WriteByte(IntPtr, Int32, Byte)	按指定偏移量将单字节值写入非托管内存。

WriteByte(Object, Int32, Byte)

Source:

Marshal.CoreCLR.cs

注意

WriteByte(Object, Int32, Byte) may be unavailable in future releases.

按指定偏移量将单字节值写入非托管内存。

public:
 static void WriteByte(System::Object ^ ptr, int ofs, System::Byte val);

[System.Obsolete("WriteByte(Object, Int32, Byte) may be unavailable in future releases.")]
public static void WriteByte (object ptr, int ofs, byte val);

[<System.Obsolete("WriteByte(Object, Int32, Byte) may be unavailable in future releases.")>]
static member WriteByte : obj * int * byte -> unit

Public Shared Sub WriteByte (ptr As Object, ofs As Integer, val As Byte)

参数

ptr

Object

非托管内存中目标对象的基址。

ofs

Int32

额外的字节偏移量，在写入前添加到 ptr 参数中。

val

Byte

要写入的值。

属性

ObsoleteAttribute

例外

AccessViolationException

基址 (ptr) 加上偏移字节 (ofs) 可产生空或无效地址。

ArgumentException

ptr 是 ArrayWithOffset 对象。 此方法不接受 ArrayWithOffset 参数。

注解

WriteByte 允许与非托管 C 样式字节数组直接交互，无需在设置其元素值之前使用 Marshal.Copy) 将整个非托管数组 (复制到单独的托管数组。

另请参阅

• Copy(Int32[], Int32, IntPtr, Int32)

WriteByte(IntPtr, Byte)

Source:

Marshal.cs

将单个字节值写入到非托管内存。

public:
 static void WriteByte(IntPtr ptr, System::Byte val);

public static void WriteByte (IntPtr ptr, byte val);

static member WriteByte : nativeint * byte -> unit

Public Shared Sub WriteByte (ptr As IntPtr, val As Byte)

参数

ptr

IntPtr

nativeint

非托管内存中要写入的地址。

val

Byte

要写入的值。

例外

AccessViolationException

ptr 不是识别的格式。

- 或 -

ptr 为 null。

- 或 -

ptr 无效。

示例

以下示例创建非托管内存块，将字节写入非托管内存，从非托管内存中读取字节，然后释放非托管内存。

using System;
using System.Runtime.InteropServices;

 class Example
 {
     static void Main(string[] args)
     {
          // Allocate 1 byte of unmanaged memory.
          IntPtr hGlobal = Marshal.AllocHGlobal(1);

          // Create a new byte.
          byte b = 1;
          Console.WriteLine("Byte written to unmanaged memory: " + b);

          // Write the byte to unmanaged memory.
          Marshal.WriteByte(hGlobal, b);

          // Read byte from unmanaged memory.
          byte c = Marshal.ReadByte(hGlobal);
          Console.WriteLine("Byte read from unmanaged memory: " + c);

          // Free the unmanaged memory.
          Marshal.FreeHGlobal(hGlobal);
          Console.WriteLine("Unmanaged memory was disposed.");
     }
}

Imports System.Runtime.InteropServices

Module Example
    Sub Main()
         ' Allocate 1 byte of unmanaged memory.
         Dim hGlobal As IntPtr = Marshal.AllocHGlobal(1)
         
         ' Create a new byte.
         Dim b As Byte = 1
         
         Console.WriteLine("Byte written to unmanaged memory: {0}", b)
         
         ' Write the byte to unmanaged memory.
         Marshal.WriteByte(hGlobal, b)
         
         ' Read byte from unmanaged memory.
         Dim c As Byte = Marshal.ReadByte(hGlobal)
         Console.WriteLine("Byte read from unmanaged memory: {0}", c)
         
         ' Free the unmanaged memory.
         Marshal.FreeHGlobal(hGlobal)
         Console.WriteLine("Unmanaged memory was disposed.")
    End Sub
End Module

注解

WriteByte 允许与非托管 C 样式字节数组直接交互，无需在设置其元素值之前使用 Marshal.Copy) 将整个非托管数组 (复制到单独的托管数组。

另请参阅

• Copy(Int32[], Int32, IntPtr, Int32)

WriteByte(IntPtr, Int32, Byte)

Source:

Marshal.cs

按指定偏移量将单字节值写入非托管内存。

public:
 static void WriteByte(IntPtr ptr, int ofs, System::Byte val);

public static void WriteByte (IntPtr ptr, int ofs, byte val);

static member WriteByte : nativeint * int * byte -> unit

Public Shared Sub WriteByte (ptr As IntPtr, ofs As Integer, val As Byte)

参数

ptr

IntPtr

nativeint

非托管内存中要写入的基址。

ofs

Int32

额外的字节偏移量，在写入前添加到 ptr 参数中。

val

Byte

要写入的值。

例外

AccessViolationException

基址 (ptr) 加上偏移字节 (ofs) 可产生空或无效地址。

示例

以下示例演示如何使用 ReadByte 和 WriteByte 方法读取和写入非托管数组。

static void ReadWriteByte()
{
    // Allocate unmanaged memory. 
    int elementSize = 1;
    IntPtr unmanagedArray = Marshal.AllocHGlobal(10 * elementSize);

    // Set the 10 elements of the C-style unmanagedArray
    for (int i = 0; i < 10; i++)
    {
        Marshal.WriteByte(unmanagedArray, i * elementSize, ((Byte)(i + 1)));
    }
    Console.WriteLine("Unmanaged memory written.");

    Console.WriteLine("Reading unmanaged memory:");
    // Print the 10 elements of the C-style unmanagedArray
    for (int i = 0; i < 10; i++)
    {
        Console.WriteLine(Marshal.ReadByte(unmanagedArray, i * elementSize));
    }

    Marshal.FreeHGlobal(unmanagedArray);

    Console.WriteLine("Done. Press Enter to continue.");
    Console.ReadLine();
}

Sub ReadWriteByte()
    ' Allocate unmanaged memory. 
    Dim elementSize As Integer = 1
    Dim unmanagedArray As IntPtr = Marshal.AllocHGlobal(10 * elementSize)

    ' Set the 10 elements of the C-style unmanagedArray
    For i As Integer = 0 To 9
        Marshal.WriteByte(unmanagedArray, i * elementSize, CType(i + 1, Byte))
    Next i
    Console.WriteLine("Unmanaged memory written.")

    Console.WriteLine("Reading unmanaged memory:")
    ' Print the 10 elements of the C-style unmanagedArray
    For i As Integer = 0 To 9
        Console.WriteLine(Marshal.ReadByte(unmanagedArray, i * elementSize))
    Next i

    Marshal.FreeHGlobal(unmanagedArray)

    Console.WriteLine("Done. Press Enter to continue.")
    Console.ReadLine()
End Sub

注解

WriteByte 允许与非托管 C 样式字节数组直接交互，无需在设置其元素值之前使用 Marshal.Copy) 将整个非托管数组 (复制到单独的托管数组。

另请参阅

• Copy(Int32[], Int32, IntPtr, Int32)