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Angular provides a CLI schematic to migrate NgStyle usages to built-in style bindings: run ng generate @angular/core:ngstyle-to-style from your project. The default migration skips some object-reference bindings because changing how Angular detects updates can alter behavior; review those cases before using the schematic’s best-effort mode.
Choose the style binding that fits the template
Angular recommends using built-in style bindings instead of NgStyle for simpler cases. They avoid importing the directive and are more straightforward; Angular’s style guide also notes that NgStyle adds performance cost compared with built-in syntax.
| What the template sets | Built-in binding | Example |
|---|---|---|
| One style property | Property binding | [style.color]="color" |
| Several style properties | Object binding | [style]="styles" |
Use the per-property form when it makes a single value clear. Use an object with [style] when the template needs to set several styles together.
Run Angular’s NgStyle migration
- From the Angular project directory, run
ng generate @angular/core:ngstyle-to-style. - Review the changed templates and the schematic’s output. The migration converts usages it considers safe by default.
- Check the resulting bindings and run the project’s usual checks to catch any unintended behavior changes.
Angular describes the schematic as one that “migrates NgStyle directive usages to style bindings in your application.” See the official NgStyle-to-style migration guide for the schematic’s instructions and options. Migration details can vary with Angular releases, so verify the guide against the version used by your project.
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Understand how the schematic changes the markup
A single style key becomes a property binding
For a one-key object, the migration can bind directly to that property:
<div [ngStyle]="{'background-color': 'red'}"></div>becomes:
<div [style.background-color]="'red'"></div>Multiple keys become one object binding
When the object contains multiple style keys, the schematic can replace [ngStyle] with a single [style] binding:
<div [ngStyle]="{'color': 'blue', 'font-weight': 'bold'}"></div>becomes:
<div [style]="{'color': 'blue', 'font-weight': 'bold'}"></div>Review object-reference bindings before using best-effort mode
A binding such as [ngStyle]="styleObject" passes an object reference rather than an inline object literal. By default, the schematic avoids object-reference usages. The optional --best-effort-mode includes them, but Angular warns this can be unsafe if the bound object is mutated.
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Before opting in, inspect how the component updates the object. If it changes properties on the same object instance, verify that the new style binding still updates the DOM as intended. If the code replaces the object instead, confirm the new binding behaves correctly in the project’s actual update flow. Do not treat a successful schematic run as proof that reference-based cases preserve runtime behavior.
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Preserve NgStyle-specific behavior where needed
NgStyle applies key-value pairs to inline styles. Its keys can include a unit suffix, such as top.px; a non-null value is applied with that unit, while a value that evaluates to null removes the corresponding style. When converting such usage, check that the new binding expresses the intended property, unit, and removal behavior. The NgStyle API reference documents the directive’s behavior and its export from CommonModule.
For details on built-in bindings, including style property and object forms, consult Angular’s template binding guide and style guide.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Keep the NgClass migration separate
NgClass is a related but distinct directive, with its own ngclass-to-class migration schematic. Do not apply the NgStyle migration to class bindings: class binding forms and their update behavior have separate considerations, documented in the NgClass API reference and Angular’s template binding guide.
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