Show/hide div if checkbox selected

问题

I need a page with checkboxes and visible div if at minimum 1 is checked.

Here I got page that if i check checkbox, the div will show. It's okay and works correctly.

When I check 3 checkboxes and uncheck 1, the div is missing, when i check some box again, the div will show - it isn't correct.

How do I need modify the script to show all time the div, if at minimum 1 checkbox is checked, without this "jumping"?

<html>
<head>
<title>CB Hide/Show</title>
<script type="text/javascript">
<!--
function showMe (it, box) {
  var vis = (box.checked) ? "block" : "none";
  document.getElementById(it).style.display = vis;
}
//-->
</script>
</head>
<body>
<h3 align="center"> This JavaScript shows how to hide divisions </h3>

<div id="div1" style="display:none">
<table border=1 id="t1">
<tr>
<td>i am here!</td>
</tr>
</table>
</div>

<form>
<input type="checkbox" name="c1" onclick="showMe('div1', this)">Show Hide Checkbox
<input type="checkbox" name="c1" onclick="showMe('div1', this)">Show Hide Checkbox
<input type="checkbox" name="c1" onclick="showMe('div1', this)">Show Hide Checkbox
<input type="checkbox" name="c1" onclick="showMe('div1', this)">Show Hide Checkbox
<input type="checkbox" name="c1" onclick="showMe('div1', this)">Show Hide Checkbox
<input type="checkbox" name="c1" onclick="showMe('div1', this)">Show Hide Checkbox
<input type="checkbox" name="c1" onclick="showMe('div1', this)">Show Hide Checkbox
<input type="checkbox" name="c1" onclick="showMe('div1', this)">Show Hide Checkbox
<input type="checkbox" name="c1" onclick="showMe('div1', this)">Show Hide Checkbox
<input type="checkbox" name="c1" onclick="showMe('div1', this)">Show Hide Checkbox
<input type="checkbox" name="c1" onclick="showMe('div1', this)">Show Hide Checkbox
<input type="checkbox" name="c1" onclick="showMe('div1', this)">Show Hide Checkbox



</form>
</body>
</html>

回答1:

change the input boxes like

<input type="checkbox" name="c1" onclick="showMe('div1')">Show Hide Checkbox
<input type="checkbox" name="c1" onclick="showMe('div1')">Show Hide Checkbox
<input type="checkbox" name="c1" onclick="showMe('div1')">Show Hide Checkbox
<input type="checkbox" name="c1" onclick="showMe('div1')">Show Hide Checkbox

and js code as

function showMe (box) {

    var chboxs = document.getElementsByName("c1");
    var vis = "none";
    for(var i=0;i<chboxs.length;i++) { 
        if(chboxs[i].checked){
         vis = "block";
            break;
        }
    }
    document.getElementById(box).style.display = vis;


}

here is a demo fiddle

回答2:

You would need to always consider the state of all checkboxes!

You could increase or decrease a number on checking or unchecking, but imagine the site loads with three of them checked.

So you always need to check all of them:

<script type="text/javascript">
<!--
function showMe (it, box) {
  // consider all checkboxes with same name
  var checked = amountChecked(box.name);

  var vis = (checked >= 3) ? "block" : "none";
  document.getElementById(it).style.display = vis;
}

function amountChecked(name) {
  var all = document.getElementsByName(name);

  // count checked
  var result = 0;
  all.forEach(function(el) {
    if (el.checked) result++;
  });

  return result;
}
//-->
</script>

回答3:

<input type="checkbox" name="check1" value="checkbox" onchange="showMe('div1')" /> checkbox

<div id="div1" style="display:none;">NOTICE</div>

  <script type="text/javascript">
<!--
   function showMe (box) {
    var chboxs = document.getElementById("div1").style.display;
    var vis = "none";
        if(chboxs=="none"){
         vis = "block"; }
        if(chboxs=="block"){
         vis = "none"; }
    document.getElementById(box).style.display = vis;
}
  //-->
</script>

来源：https://stackoverflow.com/questions/18421082/show-hide-div-if-checkbox-selected

标签

javascript

jquery

dom-events