本文整理匯總了C#中Microsoft.Win32.SafeHandles.SafeFileHandle.SafeFileHandle構造函數的典型用法代碼示例。如果您正苦於以下問題：C# SafeFileHandle構造函數的具體用法？C# SafeFileHandle怎麽用？C# SafeFileHandle使用的例子？那麽, 這裏精選的構造函數代碼示例或許可以為您提供幫助。您也可以進一步了解該構造函數所在類Microsoft.Win32.SafeHandles.SafeFileHandle的用法示例。
在下文中一共展示了SafeFileHandle構造函數的1個代碼示例，這些例子默認根據受歡迎程度排序。您可以為喜歡或者感覺有用的代碼點讚，您的評價將有助於係統推薦出更棒的C#代碼示例。
示例1: Main
//引入命名空間
using System;
using Microsoft.Win32.SafeHandles;
using System.Runtime.InteropServices;
using System.ComponentModel;
class SafeHandlesExample
{
static void Main()
{
try
{
UnmanagedFileLoader loader = new UnmanagedFileLoader("example.xml");
}
catch (Exception e)
{
Console.WriteLine(e);
}
Console.ReadLine();
}
}
class UnmanagedFileLoader
{
public const short FILE_ATTRIBUTE_NORMAL = 0x80;
public const short INVALID_HANDLE_VALUE = -1;
public const uint GENERIC_READ = 0x80000000;
public const uint GENERIC_WRITE = 0x40000000;
public const uint CREATE_NEW = 1;
public const uint CREATE_ALWAYS = 2;
public const uint OPEN_EXISTING = 3;
// Use interop to call the CreateFile function.
// For more information about CreateFile,
// see the unmanaged MSDN reference library.
[DllImport("kernel32.dll", SetLastError = true, CharSet = CharSet.Unicode)]
static extern IntPtr CreateFile(string lpFileName, uint dwDesiredAccess,
uint dwShareMode, IntPtr lpSecurityAttributes, uint dwCreationDisposition,
uint dwFlagsAndAttributes, IntPtr hTemplateFile);
private SafeFileHandle handleValue = null;
public UnmanagedFileLoader(string Path)
{
Load(Path);
}
public void Load(string Path)
{
if (Path == null && Path.Length == 0)
{
throw new ArgumentNullException("Path");
}
// Try to open the file.
IntPtr ptr = CreateFile(Path, GENERIC_WRITE, 0, IntPtr.Zero, OPEN_EXISTING, 0, IntPtr.Zero);
handleValue = new SafeFileHandle(ptr, true);
// If the handle is invalid,
// get the last Win32 error
// and throw a Win32Exception.
if (handleValue.IsInvalid)
{
Marshal.ThrowExceptionForHR(Marshal.GetHRForLastWin32Error());
}
}
public SafeFileHandle Handle
{
get
{
// If the handle is valid,
// return it.
if (!handleValue.IsInvalid)
{
return handleValue;
}
else
{
return null;
}
}
}
}