How to access nested JSON property based on another property's value in JavaScript?

JavascriptWeb DevelopmentObject Oriented Programming

To access nested JSON property based on another property’s value, the code is as follows −


var actualJSONData = JSON.parse(studentDetails()),
studentMarks = getMarksUsingSubjectName(actualJSONData, "JavaScript");
console.log("The student marks="+studentMarks);
function getMarksUsingSubjectName(actualJSONData, givenSubjectName){
   for(var tempObj of actualJSONData){
      if(tempObj.subjectName = givenSubjectName){
         return tempObj.marks;
function studentDetails(){
   return JSON.stringify(
         { firstName : "John", subjectName: "JavaScript", marks : 97 },
         { firstName : "David", subjectName: "Java", marks : 98 }

To run the above program, you need to use the following command −

node fileName.js.

Here, my file name is demo155.js.


This will produce the following output −

PS C:\Users\Amit\JavaScript-code> node demo155.js
The student marks=97
Published on 12-Sep-2020 10:58:17