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JavaScript

Posted by Tani Huang
Tani Huang
6,952 Points

Whats wrong with my code...(querySelector)

<h1 id="h1">Welcome to my page</h1>
<p>Hello my name is Tani, welcome to my page.</p>
<ul class="list reset">
 <li><a href="" title="1">1</a></li>
 <li><a href="" title="2">2</a></li>
 <li><a href="" title="3">3</a></li>
 <li><a href="" title="4">4</a></li>
 <li><a href="" title="5">5</a></li>
</ul>
<input type="text">
<button class="btn">start</button> 

var btn = document.querySelector(".btn");
btn.addEventListener("click",() => {
    document.getElementById("h1").style.color = "red";
    document.getElementById("h1").style.color = document.querySelector("input").value;
    document.querySelector("[title=1]").style.backgroundColor = "pink";
    document.querySelectorAll(".list li:nth-child(even)").style.backgroundColor = "red";
});

I have been checked many times but querySelector won't change the background Color...

2 Answers

Ryan Beckett
Ryan Beckett
14,921 Points
Ryan Beckett
Ryan Beckett
14,921 Points

You're missing the anchor tag and the quote marks. 

document.querySelector("a[title='1']").style.backgroundColor = "pink";
Steven Parker
Steven Parker
230,274 Points
Steven Parker
Steven Parker
230,274 Points

Even if your target is a single element, the "querySelectorAll" function returns a collection which does not have a "style" property. You can add an index to select a specific element from the collection, but if you want the first one you can simplify the code by using "querySelector" instead, which does return a single element.