判断文件是否打开

using System.IO; 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，你就不要拿来耍了"); 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！"); }