Module vx-hooks/usePrevious

usePrevious

• usePrevious<T>(initVal: T, compare?: (val?: T, oldVal?: T) => boolean): UsePreviousAPI<T>

• 缓存器

  typepropm

  T 值类型

  example

   const initVal = 0
   const compare = (__?: number, oldVal?: number) => {
     console.log(oldVal, oldVal === undefined || oldVal < 10)
     return oldVal === undefined || oldVal < 10
   }
   const { curRef, prevRef } = usePrevious<number>(initVal, compare)
   console.log(curRef.value) // 0
   console.log(prevRef.value) // undefined
  
   const target1 = curRef.value = 5
   console.log(curRef.value) // 5
   console.log(prevRef.value) // 0
  
   const target2 = curRef.value = 12
   console.log(curRef.value) // 12
   console.log(prevRef.value) // 5 
   
   const target3 = curRef.value = 15
   console.log(curRef.value) // 5
   console.log(prevRef.value) // 12
  
  

  Type parameters

  • T

  Parameters

  • initVal: T

    初始值

  • Optional compare: (val?: T, oldVal?: T) => boolean

    更新判断函数

    • • (val?: T, oldVal?: T): boolean

      • Parameters

        • Optional val: T

        • Optional oldVal: T

        Returns boolean

  Returns UsePreviousAPI<T>