RuntimeHelpers 类

定义

public ref class RuntimeHelpers abstract sealed

public ref class RuntimeHelpers sealed

public static class RuntimeHelpers

[System.Serializable]
public sealed class RuntimeHelpers

type RuntimeHelpers = class

[<System.Serializable>]
type RuntimeHelpers = class

Public Class RuntimeHelpers

Public NotInheritable Class RuntimeHelpers

继承

Object

RuntimeHelpers

属性

SerializableAttribute

示例

以下示例演示如何使用 PrepareConstrainedRegions 方法可靠地设置句柄。 若要可靠地将句柄设置为指定的预先存在的句柄，必须确保本机句柄的分配以及 SafeHandle 对象中该句柄的后续记录是原子的。 这些操作（如线程中止或内存不足异常）之间的任何失败都将导致本机句柄泄露。 可以使用 PrepareConstrainedRegions 方法确保句柄未泄露。

[StructLayout(LayoutKind.Sequential)]
struct MyStruct
{
    public IntPtr m_outputHandle;
}

sealed class MySafeHandle : SafeHandle
{
    // Called by P/Invoke when returning SafeHandles
    public MySafeHandle()
        : base(IntPtr.Zero, true)
    {
    }

    public MySafeHandle AllocateHandle()
    {
        // Allocate SafeHandle first to avoid failure later.
        MySafeHandle sh = new MySafeHandle();

        RuntimeHelpers.PrepareConstrainedRegions();
        try { }
        finally
        {
            MyStruct myStruct = new MyStruct();
            NativeAllocateHandle(ref myStruct);
            sh.SetHandle(myStruct.m_outputHandle);
        }

        return sh;
    }

<StructLayout(LayoutKind.Sequential)> _
Structure MyStruct
    Public m_outputHandle As IntPtr
End Structure 'MyStruct


NotInheritable Class MySafeHandle
    Inherits SafeHandle

    ' Called by P/Invoke when returning SafeHandles
    Public Sub New()
        MyBase.New(IntPtr.Zero, True)

    End Sub


    Public Function AllocateHandle() As MySafeHandle
        ' Allocate SafeHandle first to avoid failure later.
        Dim sh As New MySafeHandle()

        RuntimeHelpers.PrepareConstrainedRegions()
        Try
        Finally
            Dim myStruct As New MyStruct()
            NativeAllocateHandle(myStruct)
            sh.SetHandle(myStruct.m_outputHandle)
        End Try

        Return sh

    End Function

属性

方法

适用于