Prefill data with custom code

In version 7, we use dependency injection for custom prefilling.

1. Create a new class

Create a new file in your app project. You can choose the name and location yourself, but use sensible namespaces. For example, Altinn.App.Logic.Instantiation or similar.

The class must implement the IInstantiationProcessor interface from Altinn.App.Core.Features.

2. Write the code for automatic filling

Implement the DataCreation method in the new class. In this method, you set up which fields should be filled out automatically and what value they should receive. This is where you can fetch data from external sources, perform calculations or other relevant logic.

See below for examples.

3. Register your class

Open Program.cs and add this line:

services.AddTransient<IInstantiationProcessor, MyFilling>();

For versions 4, 5, and 6, custom prefilling is implemented in InstantiationHandler.cs.

1. Find the correct file

Go to the App/logic folder in your app project and open the file InstantiationHandler.cs.

2. Implement the DataCreation method

Write your code in the DataCreation method. Here you set up which fields should be filled out automatically and what value they should receive. This is where you can fetch data from external sources, perform calculations or other relevant logic.

See below for examples.

Example: Retrieve organization number and name from the Central Coordinating Register for Legal Entities

This fills in the Organization.OrgNr field with a custom organization number:

Note that the field names here are just imaginary examples, adapt to your needs/data.

using System.Collections.Generic;
using System.Threading.Tasks;
using Altinn.App.Core.Features;
using Altinn.App.Models;
using Altinn.Platform.Storage.Interface.Models;

namespace Altinn.App.Logic.Instantiation;

public class MyFilling : IInstantiationProcessor
{
    public async Task DataCreation(Instance instance, object data, Dictionary<string, string> prefill)
    {
        if (data is DataModel form)
        {
            form.Organization = new Organization
            {
                OrgNr = "987654321",
                Name = "TestOrganization"
            };
        }

        await Task.CompletedTask;
    }
}

Example: Retrieve personal identification number and name from the National Population Register

This fills in the Person.PersonalId field with a personal identification number and the Person.Name field with a name.

Note that the field names here are just imaginary examples, adapt to your needs/data.

using System.Collections.Generic;
using System.Threading.Tasks;
using Altinn.App.Core.Features;
using Altinn.App.Models;
using Altinn.Platform.Storage.Interface.Models;

namespace Altinn.App.Logic.Instantiation;

public class MyFilling : IInstantiationProcessor
{
    public async Task DataCreation(Instance instance, object data, Dictionary<string, string> prefill)
    {
        if (data is DataModel form)
        {
            form.Person = new Person
            {
                Personnr = "11223345678",
                Navn = "Test Testesen"
            };
        }

        await Task.CompletedTask;
    }
}

Example: Retrieve organization number and name from the Central Coordinating Register for Legal Entities

This fills in the Organization.OrgNr field with a custom organization number:

Note that the field names here are just imaginary examples, adapt to your needs/data.

public async Task DataCreation(Instance instance, object data)
{
    if (data is DataModel form)
    {
        form.Organization = new Organization
        {
            OrgNr = "987654321",
            Name = "TestOrganization"
        };
    }
}

Example: Set personal identification number and name

This fills in the Person.PersonalId field with a personal identification number and the Person.Name field with a name.

Note that the field names here are just imaginary examples, adapt to your fields/data.

    public async Task DataCreation(Instance instance, object data)
{
    if (data is DataModel form)
    {
        form.Person = new Person
        {
            PersonalId = "11223345678",
            Name = "Test Testesen"
        };
    }
}