Kristiyan Kostadinov b75e90f809 fix(forms): incorrectly keeping track of ngModel with ngFor inside a form (#40459)
When an `NgModel` is created within a `form`, it receives an `NgControl` based on its `name`, but
the control doesn't get swapped out if the name changes. This can lead to problems if the `NgModel`
is part of an `ngFor`, because the name can change based on its position in the list and a new
control can be defined with the same name, leading us to having multiple directives pointing to
the same control. For example, if we start off with a list like :

```
[0, 1, 2]; -> [NgModel(0), NgModel(1), NgModel(2)]
```

Then we remove the second item:

```
[0, 2]; -> [NgModel(0), NgModel(2)]
```

And finally, if we decide to add an item to the end of the list, we'll already have a control for
index 2, causing the list to look like:

```
[0, 2, 3]; -> [NgModel(0), NgModel(2), NgModel(2)]
```

These changes fix the issue by removing the old control when the `name` of the directive changes.

Fixes #38465.
Fixes #37920.

PR Close #40459
2022-02-07 13:16:10 -08:00
…
…
2022-01-04 12:05:25 -08:00
2022-01-04 12:05:45 -08:00

Angular - The modern web developer's platform.

angular-logo
Angular is a development platform for building mobile and desktop web applications
using Typescript/JavaScript and other languages.

www.angular.io

Contributing Guidelines · Submit an Issue · Blog

CI status   Angular on npm   Discord conversation


Documentation

Get started with Angular, learn the fundamentals and explore advanced topics on our documentation website.

Advanced

Development Setup

Prerequisites

Setting Up a Project

Install the Angular CLI globally:

npm install -g @angular/cli

Create workspace:

ng new [PROJECT NAME]

Run the application:

cd [PROJECT NAME]
ng serve

Angular is cross-platform, fast, scalable, has incredible tooling, and is loved by millions.

Quickstart

Get started in 5 minutes.

Ecosystem

angular ecosystem logos

Changelog

Learn about the latest improvements.

Upgrading

Check out our upgrade guide to find out the best way to upgrade your project.

Contributing

Contributing Guidelines

Read through our contributing guidelines to learn about our submission process, coding rules and more.

Want to Help?

Want to report a bug, contribute some code, or improve documentation? Excellent! Read up on our guidelines for contributing and then check out one of our issues labeled as help wanted or good first issue.

Code of Conduct

Help us keep Angular open and inclusive. Please read and follow our Code of Conduct.

Community

Join the conversation and help the community.

Love Angular badge

Love Angular? Give our repo a star ⭐ ⬆️.

S
Description
Generates Angular code and provides architectural guidance. Trigger when creating projects, components, services, or HTTP communication, or for best practices…
Readme MIT 1 GiB
Languages
TypeScript 81.7%
JavaScript 12.8%
HTML 2%
Starlark 1.8%
CSS 1%
Other 0.7%