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Bartosz Pietrucha for Angular

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[Pro-Tip] Angular Input syntax

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When you use [input]="value" then Angular interprets the value as an expression. So you can place there a variable reference from the component or even mathematic formula. When you use input="value" then the value is interpreted as a string! Take a look at the example:

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Top comments (3)

peterdavidcarter profile image
Peter David Carter • Edited

Important to note as the conventional understanding is that bracketed syntax represents a binding and non-bracketed a static value. As such you might expect foo="false" to be false, but in fact, since it's a string, TypeScript/JavaScript will interpret it as truthy. Counter-intuitively, static value booleans require the square bracket 'binding' syntax.

yonnyviz profile image
Yonny Vizcaya

Great tip!. This actually happened to me long time ago, I was trying to pass a string instead of a component's property; Took me almost 30min to figure that out hehe, I guess I learned the hard way. Cheers. Thanks for sharing.

bartosz_io profile image
Bartosz Pietrucha