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JavaScript JavaScript Loops, Arrays and Objects Tracking Data Using Objects The Student Record Search Challenge

Nathan Marshall
Nathan Marshall
6,019 Points

How does JavaScript know to match a searched name to [i] / a number

Hi Guys,

I have managed to complete the challenge, it seems to be working on my end but I don't understand why it works? I don't understand how javascript knows how to match the searched name to a number ( students[i] )?

If someone could take a moment to explain this to me, please?

My code is below

Thanks,

Nathan

var students = [

{ name:'Corey', track:'Web Design' , achievements: 234, points: 7000,

}, { name:'Micheal', track:'Front End Development', achievements: 344, points: 7870,

}, { name:'Jason', track:'Back End Development' , achievements: 435, points: 10234,

}, { name:'Daniel', track:'Ios Development' , achievements: 3435, points: 234254,

}, { name:'Johnny', track:'Full Stack JavaScript' , achievements: 3736, points: 343542,

},

];

function print(message){

var outputDiv = document.getElementById('output');
outputDiv.innerHTML+=message

}

while (true){

  var search = prompt('Search student records: type a name [Jody] (or type "quit" to end)');  

    for (var i = 0; i< students.length; i++){

      if (search === students[i].name ){

        alert('match found')

         print('<li>' + '<strong>' + 'Student: '+ students[i].name + '</strong>' + '</li>');
         print('<li>' + 'Track: '+ students[i].track + '</li>');
         print('<li>' + 'Achivements: '+ students[i].achievements + '</li>');
         print('<li>' + 'Points: '+ students[i].points + '</li>' + '<br>'+'<br>');

      }

    }


      if ( search.toLowerCase() === 'quit') {
        alert('You have successfully quit');
        break;
      }

}

1 Answer

With your for loop you are adding 1 to i each time the loop happens, which is after any time the prompt is answered. if (search === students[i].name ) is inside of that for loop, which means if the first item which will be students[0].name due to i starting equal to 0, the first item in the array, then the code inside your if block will trigger. So, if you searched Daniel, the if statement while debugging would be something like if ( search === students[3].name) Which would match up with Daniel as you're specifically targeting the name field on the objects in the array.