Basic JS: Profile Lookup

1

Basic JS: Profile Lookup
Ok. I know, how to do this challenge with “for” loop, but I want do it with “while” loop.
I almost done, except this instruction (“Bob”, “number” should return “No such contact”).

The code with “for”:

for (var i = 0; i < contacts.length; i++){
    if (contacts[i].firstName === firstName) {
        if (contacts[i].hasOwnProperty(prop)) {
            return contacts[i][prop];
        } else {
            return "No such property";
         }
    }
}
return "No such contact";

My code with “while”:

var i = 0;
  while (i <= contacts.length) {
    if (contacts[i].firstName === firstName)) {
        if (contacts[i].hasOwnProperty(prop)) {
                return contacts[i][prop];
         } else {
             return "No such property";
           }
    }
    i++;
  }

So, my question is: how to carry out this instruction “Bob”, “number” should return “No such contact”?

2

I think the condition in the while-loop should be a <, not a <=. You also don’t have a return 'No such contact'; after your while-loop.

3

“<” or “<=” - work both.
return “No such contact” after while-loop - not working.

4

I just tried it with a while loop. I used < and added return 'No such contact'; after the loop and it passed.

You should be able to replace a for-loop with a while loop like this:

for (var i = 0; i < contacts.length; i++) {
  // loop body
}

does the same thing as

var i = 0;
while (i < contacts.length) {
  // loop body
  i++;
}

Also, this might sound silly, but you have an extra ) in the line with the if.

1 Like
5

Great thank’s, kevcomedia!
I dont know, why this is didn’t work befor, but right now it is!
I think, that I put the “return” in the wrong place.

6

Yep, the problem was in “<” vs “<=”.
Thank’s a lot!

7

Hello,
I face the same issue. What i wrote is

for (i=0; i<contacts.length; i++) {
if (contacts[i][“firstName”]==firstName && contacts[i].hasOwnProperty(prop)) {
return contacts[i][prop];
}
}

for (i=0; i<contacts.length; i++) {
if (contacts[i][“firstName”]!=firstName) {
return “No such contact”;
}
}

for (i=0; i<contacts.length; i++) {
if (contacts[i].hasOwnProperty(prop)) {
return 0;
} else {
return “No such property”;
}
}

However, the last issue, no such a property, is not correct:

“Akira”, “address” should return “No such property”

What’s wrong in the logic of the code?

9 
for (var i = 0; i < contacts.length; i++){
    if (contacts[i].firstName === firstName) {
        if (contacts[i].hasOwnProperty(prop)) {
            return contacts[i][prop];
        } else {
            return "No such property";
         }
    }
}
return "No such contact";

Read this code and try to understand it.

2 Likes
10

I thought something similar but your code is beter.
Thank you for your response.

11