Reference to the current object in a lambda expression

Question

Is it possible to reference to a property of the current object in a Select statement of a lambda expression in Linq?

Example:

...
.Select(s => new { 
                    Date = s.Date.ToString("yyyy-MM-dd"),
                    Time = s.Time.ToString("h':'m"), 
                    DateTime = s.Date.ToString("yyyy/MM/dd") +"-"+ s.Time.ToString("h':'m"),
                    Temperature = s.Temperature,
                    Humidity = s.Humidity, 
                    Device = s.Device.Name, 
                    Message = s.Message 
                })

I would like to replace the double call to the ToString function by referencing the previously defined Date and Time properties.

Answer 1

If you switch to LINQ query syntax (instead of method syntax), you could use the let keyword "to store the result of a sub-expression in order to use it in subsequent clauses".

from s in source
let dateStr = s.Date.ToString("yyyy-MM-dd")
let timeStr = s.Time.ToString("h':'m")
select new { 
    Date = dateStr,
    Time =  timeStr, 
    DateTime = dateStr + "-" + timeStr,
    Temperature = s.Temperature,
    Humidity = s.Humidity, 
    Device = s.Device.Name, 
    Message = s.Message 
}