TS 类型转换

[xiayy860612]

• https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Number#number_%E5%BC%BA%E5%88%B6%E8%BD%AC%E6%8D%A2
• https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Boolean#%E6%8F%8F%E8%BF%B0

[xiayy860612]

const arrayWithFalsyValues: (string | null | undefined)[] = ['a', null, 'b', '', 'c', undefined, 'd'];

const filteredArray = arrayWithFalsyValues.filter(Boolean);

// filteredArray will be: ['a', 'b', 'c', 'd']

const isNotNullOrUndefined = <T>(value: T): value is NonNullable<T> => Boolean(value);

const filteredArray = arrayWithFalsyValues.filter(isNotNullOrUndefined);

// filteredArray will be: ['a', 'b', 'c', 'd']