C# 打开文件夹（如果已打开则置前，而不是再打开一个新的） 并选中指定文件 shell32.dll SHOpenFolderAndSelectItems

static public class Win32Helper
{

/// <summary>
        /// 释放命令行管理程序分配的ITEMIDLIST结构
        /// Frees an ITEMIDLIST structure allocated by the Shell.
        /// </summary>
        /// <param name="pidlList"></param>
        [DllImport("shell32.dll", ExactSpelling = true)]
        public static extern void ILFree(IntPtr pidlList);
        /// <summary>
        /// 返回与指定文件路径关联的ITEMIDLIST结构。
        /// Returns the ITEMIDLIST structure associated with a specified file path.
        /// </summary>
        /// <param name="pszPath"></param>
        /// <returns></returns>
        [DllImport("shell32.dll", CharSet = CharSet.Unicode, ExactSpelling = true)]
        public static extern IntPtr ILCreateFromPathW(string pszPath);
        /// <summary>
        /// 打开一个Windows资源管理器窗口，其中选择了特定文件夹中的指定项目。
        /// Opens a Windows Explorer window with specified items in a particular folder selected.
        /// </summary>
        /// <param name="pidlList"></param>
        /// <param name="cild"></param>
        /// <param name="children"></param>
        /// <param name="dwFlags"></param>
        /// <returns></returns>
        [DllImport("shell32.dll", ExactSpelling = true)]
        public static extern int SHOpenFolderAndSelectItems(IntPtr pidlList, uint cild, IntPtr children, uint dwFlags);

} 

调用示例
完整文件路径：E:\svn\A\B\C\D\E\2020-06-29
需求：资源管理器定位至 E:\svn\A\B\C\D\E 同时选中 2020-06-29

/// <summary>
        /// 打开目录并选中相应文件
        /// </summary>
        /// <param name="fileFullName"></param>
        static public void OpenFolderAndSelectFile(string fileFullName)
        {
            if (fileFullName.IsNullOrEmpty())
                throw new ArgumentNullException(nameof(fileFullName));
            fileFullName = Path.GetFullPath(fileFullName);
            var pidlList = Win32Helper.ILCreateFromPathW(fileFullName);
            if (pidlList == IntPtr.Zero) return;
            try
            {
                Marshal.ThrowExceptionForHR(Win32Helper.SHOpenFolderAndSelectItems(pidlList, 0, IntPtr.Zero, 0));
            }
            finally
            {
                Win32Helper.ILFree(pidlList);
            }
        }