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JavaScript Introduction to Programming Objects and Arrays Arrays

Farid Lavizadeh
Farid Lavizadeh
12,006 Points
Posted by Farid Lavizadeh
Farid Lavizadeh
12,006 Points

How is the last array item shown when value "4" was changed to friends.length?

When he has 4 friends, the value of condition in the loop is 4. He adds a new friend and changes the condition to " i < friends.length". The value of friends.length should still be 4. No? If so how is the last name "jon" is displayed?

My understanding is that for it to work it should say "i =< friends.length". What am I missing here?

3 Answers

Hugo Paz
Hugo Paz
15,622 Points
Hugo Paz
Hugo Paz
15,622 Points

Hi Farid,

Its due to the fact that an array always starts at 0.

friend.length returns 5 because there are 5 names in the array, so in reality you have i<5.

So when the for loop runs through the array it goes like this,

friends[0], friends[1], friends[2], friends[3], friends[4] which is 'Jon'.

Farid Lavizadeh
Farid Lavizadeh
12,006 Points
Farid Lavizadeh
Farid Lavizadeh
12,006 Points

Oh so unlike Array value, Length value starts with one. Thank you so much. Somehow I assumed the Length also starts with 0. Duh me.

Prabhakar acharya
PLUS
Prabhakar acharya
Courses Plus Student 2,801 Points
Prabhakar acharya
Prabhakar acharya
Courses Plus Student 2,801 Points

object.length is a good way to display array, we can keep adding object to the array and .length method will give you exactly how many object are stored. he used i<4 because we know we have 4 objects in array, if the size of the array increases then i<4 will still display 4 objects, so in this case in order to display all the objects .length is best method.