Determine in depth whether the property exists in the object

     const obj = {
        B:0.A: {C:' '.D: {F:' '}}}const attrs = [
        'C'.'A.B'.'A.C'.'A.C.D.F'
      ]
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demand

Given the key value string that meets the hierarchical structure, check whether the object has the attribute. For example, ‘A.B.C’ checks whether the object has the attribute A, whether A has the attribute B, and whether B has the attribute C.

hasOwnProperty

HasOwnProperty can be used to determine whether it has an attribute, but this is only for objects with a lower level of hierarchy. Not if you want to judge the properties of deep nodal structures

Implementation approach

For example ‘A.B.C’, check whether A exists in the object first, if so, proceed to the next level, and so on. If there is no A, then there is no need to determine the next level. The important thing to note is that we are only determining the existence of the property, not the value of the property. For example, if C: false, then the result is also true

The implementation code

function keysCheck (obj, attrs) {
      try {
        attrs.forEach((item) = > {
          let objKeys = Object.keys(obj)
          let objCopy = obj
          const attrItemList = item.split('. ')
          for (let y = 0; y < attrItemList.length; y++) {
            if (y == attrItemList.length - 1) {
              if (objKeys.includes(attrItemList[y])) throw new Error(item)
            }
            objCopy = objCopy[attrItemList[y]]
            if(! objCopy)break
            objKeys = Object.keys(objCopy)
          }
        })
      } catch (error) {
        return true
      }
      return false
    }
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