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Angular–Output enum as string in your component html

TypeScript supports 2 types of enums:

  • Numeric enums
  • String enums

From the documentation:

Numeric enums

An enum can be defined using the enum keyword.

enum Direction {
    Up = 1,
    Down,
    Left,
    Right,
}

Above, we have a numeric enum where Up is initialized with 1. All of the following members are auto-incremented from that point on. In other words, Direction.Up has the value 1, Down has 2, Left has 3, and Right has 4.

Numeric enums can be mixed in computed and constant members (see below).

String enums

String enums are a similar concept, but have some subtle runtime differences as documented below. In a string enum, each member has to be constant-initialized with a string literal, or with another string enum member.

enum Direction {
    Up = "UP",
    Down = "DOWN",
    Left = "LEFT",
    Right = "RIGHT",
}

While string enums don’t have auto-incrementing behavior, string enums have the benefit that they “serialize” well. In other words, if you were debugging and had to read the runtime value of a numeric enum, the value is often opaque - it doesn’t convey any useful meaning on its own (though reverse mapping can often help), string enums allow you to give a meaningful and readable value when your code runs, independent of the name of the enum member itself.

In my situation I was using a Numeric enum but I wanted to display the related name on the screen(in my situation a Status value):

To display this value in a View I had to use some extra magic:

  • First I had to import the enum in the corresponding component file:
  • Next step was to create a public property on the component class that exposes this type:
  • Now I can access this property on my view and get the enum string value:

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