reactjs - React - how to show the difference between the current and next props? -


i want show difference between components current , next props. example:

componentwillreceiveprops(nextprops) {     let diff = somefunction(this.props, nextprops);     console.log(diff); }

how done?

you can shallow comparison function following (i'm using es6):

function compareobjects (objecta, objectb) {     if (objecta === objectb) {         return true // return true if both variables referencing same object     }      let key      // check property objecta have objectb has not     (key in objecta) {          if (objecta.hasownproperty(key) && !objectb.hasownproperty(key)) {               return false // return false if there's difference          }     }      // check property objectb have objecta has not     (key in objectb) {          if (objectb.hasownproperty(key) && !objecta.hasownproperty(key)) {               return false // return false if there's difference          }     } }

note shallow checking , comparison on first level. compares if objects given consist of same values (therefore it's called shallow).


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