How to change Sitecore field value based on another field(s)

Question

Is there a way to dynamically change the value of a field in Sitecore based on other fields' values, something like computed fields in RDBMS?

For example, let's say we have a template that has the following fields:

• First Name
• Last Name
• Full Name

What I need to accomplish here is to change Full Name everytime a First Name or Last Name has changed.

Answer 1

If you really need to dynamically change value of Full Name field, you can create your own ItemSave handler which will change this field for particular item templates.

You can use something similar:

public class CustomItemSaveEventHandler
{
    //master database name
    public static readonly string Master = "master";
    //sample template id
    public static readonly string TemplateIdItem = "{your_template_id_goes_here}";

    public void OnItemSaved(object sender, EventArgs args)
    {
        Item item = Event.ExtractParameter(args, 0) as Item;
        if (item != null && item.Database.Name.ToLower() == Master)
        {
            if (item.TemplateID.ToString() == TemplateIdItem )
            {
                item.Editing.BeginEdit();
                item.Fields["Full Name"] = item.Fields["First Name"] + " " + item.Fields["Last Name"];
                item.Editing.EndEdit();
                item.Editing.AcceptChanges();
            }
        }
    }
}

Add some logic when First or Last names are missing and so on.

Don't forget to create a patch file :

<?xml version="1.0"?>
<configuration xmlns:patch="http://www.sitecore.net/xmlconfig/">
  <sitecore>
    <events>
      <event name="item:saved">
        <handler type="MyAssembly.MyNamespace.CustomItemSaveEventHandler, MyAssembly" method="OnItemSaved">
        </handler>
      </event>
    </events>
  </sitecore>
</configuration>