我想问一下有没有办法缩短这个三元语句？

Question

I would like to know the possibilities on how to shorten ternary statement here? TIA

data_items.attributes.promo_banner.promo_join_button_style === 'primary-flat' ? 'primary-flat' : data_items.attributes.promo_banner.promo_join_button_style === 'secondary-flat' ? 'secondary-flat' : data_items.attributes.promo_banner.promo_join_button_style === 'tertiary-flat' ? 'tertiary-flat' : data_items.attributes.promo_banner.promo_join_button_style === 'primary-animated' ? 'primary-animated' : data_items.attributes.promo_banner.promo_join_button_style === 'secondary-animated' ? 'secondary-animated' : data_items.attributes.promo_banner.promo_join_button_style === 'tertiary-animated' ? 'tertiary-animated' : 'error' "

Answer 1

For readability use a shorter variable name to store the value. Then, since you are returning the input value when it matches one of the styles, you can put the styles into an array, and then you can use Array.includes to test them all at once:

button_styles = ['primary-flat', 'secondary-flat', 'tertiary-flat', 'primary-animated', 'secondary-animated', 'tertiary-animated' ];

promo_button_style = data_items.attributes.promo_banner.promo_join_button_style;

button_styles.includes(promo_button_style) ? promo_button_style : 'error'

Note that for large arrays a Set (with has ) would be more efficient:

button_styles = new Set(['primary-flat', 'secondary-flat', ...])

button_styles.has(promo_button_style) ? promo_button_style : 'error'

Answer 2

You can do something like this:

const dataStyle = data_items.attributes.promo_banner.promo_join_button_style;

dataStyle === "primary-flat"
  ? "primary-flat"
  : dataStyle === "secondary-flat"
  ? "secondary-flat"
  : dataStyle === "tertiary-flat"
  ? "tertiary-flat"
  : dataStyle === "primary-animated"
  ? "primary-animated"
  : dataStyle === "secondary-animated"
  ? "secondary-animated"
  : dataStyle === "tertiary-animated"
  ? "tertiary-animated"
  : "error";

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Btw you should not use such long ternary operators. For such code try using a switch statement.