# Creating a DTO

Let's see this with an example. In this case we will create a mapper for a Button model.

First we need a DTO. A DTO is Plain Old C# Object (POCO). In this example our DTO will be like the following:

A DTO class **must** use a `DataTransfer` attribute from `Mobilize.WebMap.Common.Attributes`.

```
    [DataTransfer("btn")]
    public class Button
    {
        public string Text { get; set; }
        public string Name { get; set; }
    }
```

Or alternatively must implement the **IDataTransfer** interface.

```
public class Button : IDataTransfer
{
public string Text { get; set; }
public string Id { get; set; }
public string MapperId { get; set; }
}
```

Follow these guidelines when creating your DTOs:

* classes should not inherit from any other classes
* use nullable types for value types. For example `int?` instead of `int`
* the name used on the `DataTransfer` attribute should be
  * unique
  * as short as possible
  * it should start with a lowercase consonant
  * it should not use vowels
  * if it is made up of several words the next word should have just its first letter in uppercase


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