Is there a shortcut to convert a model to a view model?

Question

I am new to c# and .NET. I am learning ASP.NET MVC 5. One thing that I am finding myself spending extra time doing in converting a model to a viewmodel.

Here is my model

public class Overview
{

    public string chain_name { get; set; }
    public int store_id { get; set; }
    public int total_attempts { get; set; }
    public int total_unique_number_called { get; set;  }
    public int total_callable { get; set; }
    public int total_completed_interviews { get; set; }

}

and here is my view model

public class OverviewViewModel
{

    public string chain_name { get; set; }
    public int store_id { get; set; }
    public int total_attempts { get; set; }
    public int total_unique_number_called { get; set; }
    public int total_callable { get; set; }
    public int total_completed_interviews { get; set; }
    public decimal? unique_number_per_complete { get; set; }

    public OverviewViewModel()
    {
        unique_number_per_complete = 0;
    }

}

as you can see both Model and ViewModel are identical except for over variable which is a calculation.

To populate my view model I do the following

var records = conn.Database.SqlQuery<Overview>(query).ToList();

var overView = new List<OverviewViewModel>();

foreach(var record in records){

    var newRecord = new OverviewViewModel();

    newRecord.store_id = record.store_id;

    newRecord.chain_name = record.chain_name;

    newRecord.total_attempts = record.total_attempts;

    newRecord.total_callable = record.total_callable;

    newRecord.total_completed_interviews = record.total_completed_interviews;

    if (record.total_completed_interviews > 0) {
        newRecord.total_unique_number_called = record.total_unique_number_called / record.total_completed_interviews;
    }

    overView.Add(newRecord);
}

The two issues that I am seeing with my approach is that

1. I have to do lots of extra coding especially of the view model is large or f I have multiple variables that I need to calculate.
2. I feel I am looping 1 extra time to convert my model to view mode.

Is there an easier way to do this in c#?

Is there a better approach with this procedure for a large application? My goal is to learn the better way to utilize my code time to the fullest.

Answer 1

I agree that you should look into automapper, but another way would be to create a constructor on your OverviewViewModel model that takes and Overview object and populates all the properties. Something like

public class OverviewViewModel {

    public string chain_name { get; set; }
    public int store_id { get; set; }
    public int total_attempts { get; set; }
    public int total_unique_number_called { get; set; }
    public int total_callable { get; set; }
    public int total_completed_interviews { get; set; }
    public decimal? unique_number_per_complete { get; set; }

    public OverviewViewModel()
    {
        unique_number_per_complete = 0;
    }
public OverviewViewModel(Overview record)
    {
        store_id = record.store_id;

    chain_name = record.chain_name;

    total_attempts = record.total_attempts;

    total_callable = record.total_callable;
    //etc
    }
}  

Then your code would look like

var overView = new List<OverviewViewModel>();

foreach(var record in records){
    overView.Add(new OverViewViewModel(record));
}