任何人都可以帮助我吗？
我尝试P/Invoke从托管的 .net 代码中使用 WINAPI 方法。
CreateFile()方法总是返回假。如果我使给定的路径小于 256，它就可以正常工作，但如果大于 256，则不会。我可能做错了什么。根据此链接，我应该能够使用长度大于 256 的长路径文件。
以下是我尝试过的代码：
static void Main(string[] args)
{
string path = @"c:\tttttttttttaaaaaaaaaaaaaaatttttttttttttttaaaaaaaaaaaaaaatttttttttttttttttttttttttttttttaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaattttttttttttttttttaaaaaaaaaaaaaaaaatttttttttttaaaaaaaaaaatttttttaaaaaaaaaaaaaaaaattttttttttttttttttaaaaaaaaaaaaaaaaattttttttttttttaaaaaaaaaaaaaaaaatttttt";
LongPath.TestCreateAndWrite(path);
}
// This code snippet is provided under the Microsoft Permissive License.
[DllImport("kernel32.dll", SetLastError = true, CharSet = CharSet.Unicode)]
internal static extern SafeFileHandle CreateFile(
string lpFileName,
EFileAccess dwDesiredAccess,
EFileShare dwShareMode,
IntPtr lpSecurityAttributes,
ECreationDisposition dwCreationDisposition,
EFileAttributes dwFlagsAndAttributes,
IntPtr hTemplateFile);
public static void TestCreateAndWrite(string fileName) {
string formattedName = @"\\?\" + fileName;
//string formattedName = @"\\?\UNC" + fileName;
// Create a file with generic write access
SafeFileHandle fileHandle = CreateFile(formattedName, EFileAccess.GenericWrite,
EFileShare.None, IntPtr.Zero, ECreationDisposition.CreateAlways, 0, IntPtr.Zero);
// Check for errors
int lastWin32Error = Marshal.GetLastWin32Error();
if (fileHandle.IsInvalid) {
throw new System.ComponentModel.Win32Exception(lastWin32Error);
}
// Pass the file handle to FileStream. FileStream will close the
// handle
using (FileStream fs = new FileStream(fileHandle,
FileAccess.Write)) {
fs.WriteByte(80);
fs.WriteByte(81);
fs.WriteByte(83);
fs.WriteByte(84);
}
}
此方法抛出错误代码 3，这是未根据系统错误代码 (0-499) (Windows) 指定的文件路径。
任何帮助都将是非常可观的。