在鼠标悬停时显示/隐藏div

Question

JavaScript:

$( document ).ready(function() {
    function show(id) {
        document.getElementById(id).style.visibility = "visible";
    }
    function hide(id) {
        document.getElementById(id).style.visibility = "hidden";
    }
});

And HTML:

<table>
    <tr>
        <td id="one">
                <div class="content" onMouseOver="show('text')"  onMouseOut="hide('text')">
                    <h1>Heading</h1>
                    <p id="text">Lorem ipsum</p>
                </div>
            </div>
        </td>
</table>

Lorem ipsum is supposed to show when the mouse hovers over the content div, but it doesn't work. It is encased in a table because there are three other content divs that make a 2 by 2 grid.

Answer 1

show is not on the global object, it's in a closure, so when your HTML event handlers tries to call it, it doesn't exist.

Use CSS instead

#text {
    visibility: hidden;
}

.content:hover #text {
    visibility: visible;
}

Answer 2

Your functions need to be in global scope, outside of document.ready :

$( document ).ready(function() {
    //...
});

function show(id) {
    document.getElementById(id).style.visibility = "visible";
}
function hide(id) {
    document.getElementById(id).style.visibility = "hidden";
}

Answer 3

You need to define your two JavaScript functions outside of the jQuery environment/scope.

See below.

 function show(id) { document.getElementById(id).style.visibility = "visible"; } function hide(id) { document.getElementById(id).style.visibility = "hidden"; } 

 .content { border: 1px dotted blue; } #text { visibility: hidden; } 

 <table> <tr> <td id="one"> <div class="content" onMouseOver="show('text');" onMouseOut="hide('text')"> <h1>Heading</h1> <p id="text">Lorem ipsum</p> </div> </div> </td> </table> 

Answer 4

It's convenient to use jQuery. Also, try not to put JavaScript directly in the HTML tags. The problem here was a scope issue.

 $(".content").hover(function() { $("#text").show(); }, function() { $("#text").hide(); }); 

 <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script> <table> <tr> <td id="one"> <div class="content"> <h1>Heading</h1> <p id="text">Lorem ipsum</p> </div> </div> </td> </table> 

Answer 5

Just define the functions outside the jQuery scope.

<script>
function show(id) {
 document.getElementById(id).style.visibility = "visible";
}
function hide(id) {
 document.getElementById(id).style.visibility = "hidden";
}
</script>