C#

[DllImport("advapi32.dll",EntryPoint = "RegQueryValueEx")]
        public static extern int RegQueryValueEx(UIntPtr hKey,stringlpValueName,int lpReserved,out uint lpType, IntPtr lpData,ref int lpcbData);

private static int ReadRegKey(UIntPtr HKEY_LOCAL_MACHINE, string lpSubKey, string valueName)
{
   LONG regReturnType = RegOpenKeyEx(HKEY_LOCAL_MACHINE, lpSubKey, 0, KEY_READ, out valueName );

   // Use ERROR_SUCCESS instead of number. I think I have read
   // documentation saying the number may change. Use ERROR_SUCCESS
   // is a sure way.
   if (regReturnType == ERROR_SUCCESS)
   {
           Console.WriteLine(valueName);
 
           int size = 1024;
           uint type;
           string keyValue = String.Empty; // Use String.Empty
           StringBuilder keyBuffer = new StringBuilder();
                
           regReturnType = RegQueryValueEx(HKEY_LOCAL_MACHINE, valueName, 0, out type, keyBuffer, ref size) 
           if (regReturnType == ERROR_SUCCESS)
           {
              keyValue = keyBuffer.ToString();
 
              Console.WriteLine(keyValue);
              // return (keyValue);
              // Passing keyValue outside the function using return
              // is wrong. If you use return, the value you capture
              // for keyValue will never get a value.
           }
           return regReturnType;
   }
   return regReturnType;      
}

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a) I cannot find the registry value you mentioned in my Win7. Are you sure the value exist somewhere? Is it in Windows server?

Quote:

b) You are not familiar with how function gets parameter from outside and how to pass parameter back to the outside world.

Quote:

please note it is supposed to return an integer

using (OleDbDataReader reader = command.ExecuteReader())
{
    while (reader.Read())
    {
        string foo = reader[0].ToString();
        string newcolumn = foo.Substring(foo.IndexOf(":") + 1);
                            
        object[] meta = new object[reader.FieldCount];
        reader.GetValues(meta);
        List<string> list = meta.ToList().ConvertAll(o => o.ToString());
    }
}

using (OleDbCommand command = connection.CreateCommand())
{
   int idx = 0;
   command.CommandText = string.Format("select * from [{0}$]", "Report_12251104");
   using (OleDbDataReader reader = command.ExecuteReader())
   {
       while (reader.Read())
       {
          string foo = reader[0].ToString();
          string newcolumn = foo.Substring(foo.IndexOf(":") + 1);
                            
          object[] meta = new object[reader.FieldCount];
          reader.GetValues(meta);
          List<object> list = meta.ToList();
          list.Insert(2,newcolumn);
       }
       OleDbCommand update = connection.CreateCommand();
       //I want 
       update.CommandText = "update ??what exactly?? Can I use idx to id a row by number??";
       update.ExecuteNonQuery();
       idx++;
    }
}