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JavaScript

akash dikkaram
akash dikkaram
1,927 Points
Posted by akash dikkaram
akash dikkaram
1,927 Points

The Build an Object Challenge, Part 2

I am Getting Undefined ???Why Is That!!?

<html>
<head><title>Challenge on loop,array,object</title></head>
<body>
<script>

 var students = [ 
 { 
 name: 'Dave',
  track: 'Front End Development',
  achievements: 158,
  points: 14730
 },
 {
 name: 'Jody',
  track: 'iOS Development with Swift',
  achievements: '175',
 points: '16375'
 },
{
 name: 'Jordan',
 track: 'PHP Development',
 achievements: '55',
 points: '2025'
},
{
name: 'John',
track: 'Learn WordPress',
achievements: '40',
points: '1950'
},
{
 name: 'Trish',
 track: 'Rails Development',
 achievements: '5',
 points: '350'
 }
 ];
 var studeent='';
 var data;

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


       studeent=students[i];
       data+='<p>'+studeent.name+'</p>';
        data+='<p>'+studeent.achievements+'</p>';
        data+='<p>'+studeent.track+'</p>';
        data+='<p>'+studeent.points+'</p>';
    }
document.write(data);

 </script>
 </body>
 </html>

1 Answer

Benjamin Barslev Nielsen
Benjamin Barslev Nielsen
18,958 Points
Benjamin Barslev Nielsen
Benjamin Barslev Nielsen
18,958 Points 
var data;

is equal to:

var data = undefined;

and 

undefined + "someString" evaluates to "undefinedsomeString"

Therefore you should declare data to be the empty string initially:

var data = "";

Hope this helps