C# 判断文件是否被占用的两种方法

其他知友问过，大神解决方法如下：
第一种方法：
using System.Runtime.InteropServices;
[DllImport(kernel32.dll)]
public static extern IntPtr _lopen(string lpPathName, int iReadWrite);
[DllImport(kernel32.dll)]
public static extern bool CloseHandle(IntPtr hObject);
public const int OF_READWRITE = 2;
public const int OF_SHARE_DENY_NONE = 0x40;
public readonly IntPtr HFILE_ERROR = new IntPtr(-1);
private void button1_Click(object sender, EventArgs e){string vFileName = @c:\temp\temp.bmp;
if (!File.Exists(vFileName)){MessageBox.Show(文件都不存在!);return;}IntPtr vHandle = _lopen(vFileName, OF_READWRITE | OF_SHARE_DENY_NONE);
if (vHandle == HFILE_ERROR){MessageBox.Show(文件被占用！);return;}CloseHandle(vHandle);
MessageBox.Show(没有被占用！);}
第二种方法：
public static bool IsFileInUse(string fileName){bool inUse = true;
FileStream fs = null;try{
fs = new FileStream(fileName, FileMode.Open, FileAccess.Read,
FileShare.None);
fs.Close();}return inUse;//true表示正在使用,false没有使用}

http://stackoverflow.com/questions/876473/is-there-a-way-to-check-if-a-file-is-in-use