html - JavaScript focus() function doesn't focus textarea on page load

I have the following code.

<!DOCTYPE html>
<html>
<head>
<title>Focus issue</title>
<script type='text/javascript'>//<![CDATA[ 
window.onload=function(){
  var text = document.getElementById('text')
  window.onload = function() {
    text.focus()
  }
  window.onhashchange = function() {
    text.focus()
  }
}//]]>  
</script>
</head>
<body>
  <textarea id="text"></textarea>
  <p><a href="#focus">Click to focus</a></p>
</body>
</html>

Here is a JSFiddle demo of the above code: /

Why doesn't the focus go on the textarea box when the page loads? On clicking the link, the focus does go on the textarea box, but I also want the focus to go to the textarea box on page load. Why doesn't it happen?

Note: I am aware of the HTML5 autofocus attribute for textarea. But this question is about why the above JavaScript code does not do what I intend to do.

I have the following code.

<!DOCTYPE html>
<html>
<head>
<title>Focus issue</title>
<script type='text/javascript'>//<![CDATA[ 
window.onload=function(){
  var text = document.getElementById('text')
  window.onload = function() {
    text.focus()
  }
  window.onhashchange = function() {
    text.focus()
  }
}//]]>  
</script>
</head>
<body>
  <textarea id="text"></textarea>
  <p><a href="#focus">Click to focus</a></p>
</body>
</html>

Here is a JSFiddle demo of the above code: http://jsfiddle/DvU63/

Note: I am aware of the HTML5 autofocus attribute for textarea. But this question is about why the above JavaScript code does not do what I intend to do.

Share Improve this question edited Sep 1, 2013 at 7:29 nnnnnn 150k30 gold badges209 silver badges247 bronze badges asked Sep 1, 2013 at 7:24 Lone Learner 20.8k25 gold badges114 silver badges221 bronze badges

I think it does work, jsfiddle/DvU63/1 – Sergio Commented Sep 1, 2013 at 7:28
@Sergio Do you have an explanation about why adding an input text field resolves the issue? – Lone Learner Commented Sep 1, 2013 at 7:29
@Sergio My question is not specific to jsfiddle. Copy paste my code in this question and paste it to a file, say, foo.html and open it with Firefox and the same issue occurs. – Lone Learner Commented Sep 1, 2013 at 7:41
Yes, I understood that after @nnnnnn called my attention. You have a scope problem and I think his explanation is the answer to your question (and should be the accepted answer). – Sergio Commented Sep 1, 2013 at 7:44

Add a ment |

2 Answers 2

Sorted by: Reset to default 5

You're doing the .focus() statement from inside an onload handler that is itself defined inside an onload handler. This inner onload will not be called because by the time you define it the onload event will have occurred. Try this:

window.onload=function(){
  var text = document.getElementById('text')
  text.focus()

  window.onhashchange = function() {
    text.focus()
  }
}

Your demo, updated: http://jsfiddle/DvU63/2/

do this

<script type='text/javascript'> 
    window.onload=function(){
    var text = document.getElementById('text')

    text.focus();

    window.onhashchange = function() {
        text.focus();
    }
  }
</script>

fiddle

科技改变生活-雨落星辰 - 所有的伟大,都源于一个勇敢的开始

html - JavaScript focus() function doesn't focus textarea on page load - Stack Overflow

2 Answers 2

与本文相关的文章

评论列表(0)