27 lines
2.0 KiB
Markdown
27 lines
2.0 KiB
Markdown
# Nested Forms - An exploration of alternatives
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The official Angular documentation discussing [Reactive Forms](https://angular.io/guide/reactive-forms) shows how one can use groups and arrays to organize a form, and to dynamically add to it. The drawback of the example on that page is that everything is in a single component.
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Once a component starts to grow in size and complexity, it becomes desirable to decompose it into multiple smaller components. At this point, there are a number of ways to break up the form into a set of nested form elements.
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# Project Purpose
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This project explores several approaches to implementing nested forms/components. The project is structured using the [Nrwl Nx](https://nx.dev/) monorepository framework, with shared models and services in a library, and separate applications to explore each approach.
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Each application implements a simple contact management form, capturing simple demographics information and a list of postal addresses.
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## Base Line - The Single component
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The [Base Line](apps/baseline) application implements the contact manangement form in a single angular component, directly using the example techniques from the [Reactive Forms](https://angular.io/guide/reactive-forms) documentation.
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## Components Creating Own Form Controls
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Searching the Internet for examples of nested forms in Angular shows one popular approach is to have each sub-component be responsible for creating its own form controls. The parent form is passed in as an `@Input`, and the component adds its components to the form using the `addControl(name, control)` method.
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The [Parent Form](apps/parent-form) application explores this approach.
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## Parent Component Creates Form and Passes Form Controls Into Child Components
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Another approach is to allow the outermost, or parent, component create the full Reactive Form. Each child component is given the `FormGroup` containing the portion of the form that it is responsible for rendering.
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The [Global Form](apps/global-form) application explores this approach. |