Get value from dictionary based on key throws error - syncfusion schedule

Question

In my ASP.NET (c#) application using syncfusion schedule, I am trying to get a value from a dictionary based on the key.

When I try to do that I get this error message:

System.Collections.Generic.KeyNotFoundException: 'The given key was not present in the dictionary.

This line of code (where I try to get the value of key 'Subject' and assign it to variable sSubject) throws the error:

string sSubject = list["Subject"].ToString();

Code:

    public Dictionary<string, object> Arguments { get; set; }

    protected void Schedule1_ServerAppointmentEdited(object sender, Syncfusion.JavaScript.Web.ScheduleEventArgs e)
    {
        Arguments = e.Arguments["appointment"] as Dictionary<string, object>;
        dynamic list = Arguments as Dictionary<string, object>;

        string sSubject = list["Subject"].ToString();
    }

If I debug my code to look what's in my dictionary, I do see that key 'Subject' is present:

What am I doing wrong? How can I get value 'test subject' from key 'subject'?

Project: http://www.syncfusion.com/downloads/support/forum/119417/ze/ScheduleCRUDWithWebServices-728709208

Documentation: https://www.syncfusion.com/kb/5182/how-to-perform-the-crud-operation-in-the-schedule-control-with-webservices-datasource

Thank you

Answer 1

This is how I finally retrieved the value of key 'subject':

Arguments = e.Arguments["appointment"] as Dictionary<string, object>;
//dynamic list = Arguments as Dictionary<string, object>;
System.Collections.ArrayList list2 = (System.Collections.ArrayList)Arguments["changed"];
Dictionary<string, object> dic = (Dictionary<string,object>)list2[0];
string sSubject2 = dic["Subject"].ToString();