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JavaScript JavaScript Loops, Arrays and Objects Tracking Data Using Objects The Build an Object Challenge, Part 2 Solution

Posted by Wojciech Samolowicz
Wojciech Samolowicz
8,265 Points

Can I use loop "for in" inside "for" loop in my solution ? 

for ( i = 1; i < Students.length; i += 1 ) {
    document.write("<h2>Student:  " + Students[i].Name + "</h2>") ;
    for ( var prop in Students[i]) {
        document.write([prop] + ": " + Students[i][prop] + "<br>" );
    }
}

2 Answers

Steven Parker
Steven Parker
216,012 Points
Steven Parker
Steven Parker
216,012 Points

You certainly can nest loops of the same or different types.

But you'll probably want to start the outer loop with "i = 0", since 0 is the index of the first item of an array. And you won't need any brackets around the word "prop" where it is used by itself.

Daniel Grigo
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Daniel Grigo
Full Stack JavaScript Techdegree Graduate 18,815 Points
Daniel Grigo
.a{fill-rule:evenodd;}techdegree seal-36
Daniel Grigo
Full Stack JavaScript Techdegree Graduate 18,815 Points

In addition, if you write down the students name in the outer loop (which I also thought of first), it will be printed again during your inner loop under the "name" property. You could get around that with an if-clause:

 for (var i=0; i<students.length; i++){
   for (var prop in students[i]){
     if (prop=="name"){
      message+="<h2>Student: " +students[i][prop]+"</h2>";
    }
    else {message+="<br>"+prop+ ": "+ students[i][prop];
    }
  }
   message+="<p></p>";
 }