获取上次打开目录

try {       dialog.SelectedPath = FolderPathHelper.GetLastPath("9009","菜单1"); }  catch (Exception ex)  {       Log($"获取路径失败：{ex.ToString()}"); #if DEBUG       throw ex; #endif }

try {      FolderPathHelper.SavePath("9009","菜单1","C:\"); } catch (Exception ex) {       Log($"保存路径失败：{ex.ToString()}"); #if DEBUG        throw ex; #endif }    

public class FolderPathHelper     {         public static string GetLastPath(string user, string menu)         {             string currentPath = Directory.GetCurrentDirectory() + "\UserPath\LastPath.csv";              if (!File.Exists(currentPath))             {                 return "";             }              var table = OpenCSVFile(currentPath);             var folder = table.AsEnumerable().FirstOrDefault(row => row["user"].ToString() == user && row["menu"].ToString() == menu)?["folder"].ToString() ?? "";             return folder;         }          public static bool SavePath(string user, string menu, string folder)         {             //判断目录是否存在             string currentPath = Directory.GetCurrentDirectory() + "\UserPath\LastPath.csv";             DataTable table;              table = OpenCSVFile(currentPath);             if (table.Rows.Count > 0)             {                 var rows = table.AsEnumerable().Where(row => row["user"].ToString() == user && row["menu"].ToString() == menu).ToList();                 foreach (var row in rows)                 {                     table.Rows.Remove(row);                 }             }                        table.Rows.Add(user, menu, folder, DateTime.Now.ToString("yyyyMMdd hhmmss"));             SaveCSV(table, currentPath);             return true;         }          public static void SaveCSV(DataTable dt, string fullPath)//table数据写入csv         {             System.IO.FileInfo fi = new System.IO.FileInfo(fullPath);             if (!fi.Directory.Exists)             {                 fi.Directory.Create();             }             using (System.IO.FileStream fs = new System.IO.FileStream(fullPath, System.IO.FileMode.Create,                 System.IO.FileAccess.Write))             using(System.IO.StreamWriter sw = new System.IO.StreamWriter(fs, System.Text.Encoding.UTF8))             {                 for (int i = 0; i < dt.Rows.Count; i++) //写入各行数据                 {                     var data = new List<string>();                     for (int j = 0; j < dt.Columns.Count; j++)                     {                         var str = dt.Rows[i][j].ToString();                         //替换英文冒号 英文冒号需要换成两个冒号                         str = str.Replace(""", """");                         //含逗号 冒号 换行符的需要放到引号中                         if (str.Contains(',') || str.Contains('"') || str.Contains('r') || str.Contains('n'))                                                 {                             str = $""{str}"";                         }                         data.Add(str);                                            }                                         sw.WriteLine(string.Join(",",data));                 }                 sw.Close();                 fs.Close();             }                        }          private static DataTable OpenCSVFile(string filepath)         {             string strpath = filepath; //csv文件的路径             var table = new DataTable();             table.Columns.Add("user");             table.Columns.Add("menu");             table.Columns.Add("folder");             table.Columns.Add("time");              if (!File.Exists(filepath))             {                 return table;             }              string strline;             string[] aryline;             using (StreamReader mysr = new StreamReader(strpath, System.Text.Encoding.Default))             {                 while ((strline = mysr.ReadLine()) != null)                 {                     aryline = strline.Split(new char[] { ',' });                     var row = table.NewRow();                     for (int i = 0; i < table.Columns.Count; i++)                     {                         row[i] = aryline[i];                     }                     table.Rows.Add(row);                 }                 return table;             }         }     }