Json Deserialize Common Format

Uttam review attachment and review logic. I sent  screenshot of whats going on in the debugger. Your logic is not accounting for all of the sendactions in the file. 
 
public Dictionary> GetSiteData(List filenames)
{
if (filenames == null)
throw new ArgumentNullException("filenames is null...");
if (filenames.Count() == 0)
throw new ArgumentOutOfRangeException("filenames count is out of range...");
Dictionary> SiteDictionary = new Dictionary>();
foreach (string f in filenames)
{
string json = File.ReadAllText(f);
string result = json.Substring(json.IndexOf('{') + 1);
var text = JsonConvert.DeserializeObject< List < SeraphimDetailRoot >> (json);
}
return null;
}

Uttam, Will this work for and entire file of send actions?

You can substring SendAction and Datetime if there is only one occurance. For multiple SendAction we may need to write different logic

string jsonData = "SendAction 2018-10-18T20:04:01.000000 { \"EventDate\"";  
string result = jsonData.Substring(jsonData.IndexOf('{'));  

Also if we can ignore the SendAction and Datetime, Everthing works smooth that way also just so you

Uttam, I need help with writing logic. There will be many records in one file that have many sendactions. So we have to make sure logic accounts for all sendactions

Can you check the json format of the the data you have received first?
The format does not look correct..

public class Detail
{
public string ApplicationGuid { get; set; }
public string ApplicationVersion { get; set; }
public string ClickItemID { get; set; }
public string Description { get; set; }
public double Discount { get; set; }
public string EventType { get; set; }
public string ItemID { get; set; }
public string ProductID { get; set; }
public string ProductName { get; set; }
public double ProductPrice { get; set; }
public string Promo { get; set; }
public int Quantity { get; set; }
public int TransAmount { get; set; }
}
public class Root
{
public DateTime EventDate { get; set; }
public string HeaderVersion { get; set; }
public List Details { get; set; }
public string Session { get; set; }
public string SiteGuid { get; set; }
public string UserEmail { get; set; }
public string UserGuid { get; set; }
public string UserID { get; set; }
}

then use 

var myDeserializedClass = System.Text.Json.JsonSerializer.DeserializeObject(myJsonResponse);