鍑芥暟寮忕紪绋婩P 鍒濇帰

Posted 2020-12-21

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 const utils = {
   //瀹氫箟鍙橀噺鏄惁瀛樺湪 js鏈変袱涓〃绀轰笉瀛樺湪鐨勫€?undefined|null  true琛ㄧず瀛樺湪 false琛ㄧず涓嶅瓨鍦?undefined|null)
   existy(val) {
     return val != null //undefined 涔熸槸鍙互鐨?

   },
   //鍒ゆ柇涓€涓彉閲忔槸鍚︾瓑鍚屼簬true=> (undefined|null|false)鍒ゅ畾false  鍏朵綑閮芥槸true.鍖呮嫭0|鈥樷€?/span>
   truthy(val) {
     return val !== false && utils.existy(val)
   },
   //婊¤冻鏉′欢涓虹湡鎵ц鎿嶄綔锛屽惁鍒欒繑鍥?/span>
   doWhen(conditon, callback) {
     if (utils.truthy(conditon)) return callback()
     return undefined
   }
 }
 module.exports = utils

 

const {
  existy,
  truthy
} = require(鈥?/utils鈥?span style="color: rgba(0, 0, 0, 1)">)

console.log([null, undefined, false, 0, 鈥樷€榏.map(item => existy(item))) // [ false, false, true, true, true ] 
console.log([null, undefined, false, 0, 鈥樷€榏.map(existy)) // [ false, false, true, true, true ] 鏄笂闈㈢殑绠€鍐欐柟寮忋€傛晥鏋滀竴鎽镐竴鏍?/span>

console.log([null, undefined, false, 0, 鈥樷€榏.map(truthy)); //[ false, false, false, true, true ]