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

Broken Exercise?

This exercise is asking me to set both parts of the value to variable inputValue but doing so will result in the first portion of the exercise to break.

app.js
let inputValue = document.querySelector("linkName").value;
index.html
<!DOCTYPE html>
<html>
    <head>
        <title>DOM Manipulation</title>
    </head>
    <link rel="stylesheet" href="style.css" />
    <body>
        <div id="content">
            <label>Link Name:</label>
            <input type="text" id="linkName">
            <a id="link" href="https://teamtreehouse.com"></a>
        </div>
        <script src="app.js"></script>
    </body>
</html>

2 Answers

This is a syntax error. When using querySelector you use css formatting to refer to an element.

let inputValue = document.querySelector("#linkName").value;

or you could use getElementById

let inputValue = document.getElementById("linkName").value;
Steven Parker
Steven Parker
229,920 Points

You haven't selected an element.

There's no element with a tag named "linkName", so the querySelector returns null. And trying to get the value attribute of null will always fail.

You have many options for how to get a reference to the proper element, here's a few (I recommend the first one):

  • document.getElementById("linkName")
  • document.querySelector("#linkName")
  • document.querySelector("input")
  • document.querySelector("[type=text]")
  • document.querySelector("#content > :nth-child(2)")
  • document.querySelectorAll("input")[0]
  • document.getElementsByTagName("input")[0]