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JavaScript JavaScript and the DOM (Retiring) Making Changes to the DOM Modifying Elements

Posted by Andrew Phythian
Andrew Phythian
19,747 Points

Why is inputValue = * incorrect, but * = inputValue is correct

To explain, in the second question the following code

let inputValue = document.getElementById('linkName').value;
inputValue = document.getElementById('link').textContent;

is incorrect, but

let inputValue = document.getElementById('linkName').value;
document.getElementById('link').textContent = inputValue;

works fine.

In other words, the placement of 'inputValue' has to be at the end of the statement?

Andrew Phythian
Andrew Phythian
19,747 Points

Unless I am mistaken, after a bit of experimentation it seems particular to this challenge. In the console if I type

let a = 15
a

the console outputs 15.

Changing a

a = 25
a

outputs 25 just fine.

1 Answer

Kristiana Georgieva
Kristiana Georgieva
14,595 Points

Hi! Here's my take on it. 

let inputValue = document.getElementById('linkName').value; 
// the variable 'inputValue ' is equal to the element with ID linkName.

inputValue = document.getElementById('link').textContent; 
// here, you are again saying that the variable 'inputValue ' 
// should be equal to an entirely different thing 
// (the text content of the element with ID link). It contradicts the line of code above.

While in the second code: 

let inputValue = document.getElementById('linkName').value; 
// the variable 'inputValue ' is equal to element with ID linkName.

document.getElementById('link').textContent = inputValue; 
// the text content of the element with ID link is equal to the  content of the 'inputValue ' variable

Hope it makes sense. Or maybe someone could explain it better :)

Good luck!

Andrew Phythian
Andrew Phythian
19,747 Points

Thanks for the reply. I was aware of the issue of 'scope' but had never considered that the placement of inputValue in the statement was important.