how to create properties with sub properties having constant values in a class using c#

Question

I would like to create a string using the StringBuilder() class. I have a collection of records of say Employees. Each record of Employee has columns such as firstName, lastName, city, etc. The string that I want to create will have the values of the above mentioned columns each. For this I need to create a class

class Columns
{
    string Firstname
    {
        startPosition = 1;
        length = 32;
    }

    string LastName
    {
        startPosition = 33;
        length = 32;
    }
}

In the string that I'm building I need to insert the values of Firstname,Lastname in the respective start positions mentioned. I'm new to this and I need help in creating the above class. The above specified code is just the prototype of what the class should be like but I do not know how exactly to create this. I need the properties startPosition and length to be present in all the columns and these values need to be hardcoded. Sorry if my question is vague. Please help..

Answer 1

Let me start with telling you, there is no such thing as "sub properties". What you can do is have a property/field of a class which exposes properties itself.

Therefore, you might want to create a class for one Column and then create a List to keep track of your Columns like in the following example.

public class Column
{
    public string Name { get; set; }
    public int StartPos { get; set; }
    public int Length { get; set; }
}

public class Test
{
    private List<Column> Columns = new List<Column>();

    public Test()
    {
        this.Columns.Add(new Column { Name = "FirstName", StartPos = 1, Length = 32 });
        this.Columns.Add(new Column { Name = "LastName", StartPos = 33, Length = 32 });
    }

    public string GetThatString(string str)
    {
        foreach (var col in this.Columns)
        {
            // Do what you need. Sample:
            var item = str.Substring(col.StartPos, col.Length);
            Console.WriteLine("{0}: {1}", col.Name, item);
        }
    }
}

You could then iterate over the items in the List and have your string builder do the work yo need. Of course, you could also create a property for each Column instead of a List of all the Columns.