javascript - Using keydown() why after first character if alert the value is empty? - Stack Overflow

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If I press (for the first time) a character, than the alert prints an empty value.

How is possible? I don't understand.

$('#search-vulc').on('keydown', function() {
  var textinsert = ($(this).val()).toLowerCase();
  alert(textinsert);
});

Please tell me how I can print it with the first time, when the character is pressed.

Here is there also a jsfiddle example:

/

If I press (for the first time) a character, than the alert prints an empty value.

How is possible? I don't understand.

$('#search-vulc').on('keydown', function() {
  var textinsert = ($(this).val()).toLowerCase();
  alert(textinsert);
});

Please tell me how I can print it with the first time, when the character is pressed.

Here is there also a jsfiddle example:

https://jsfiddle/06xg4c78/1/

• javascript
• jquery
• keypress
• keydown

Share Improve this question Follow edited Jun 5, 2018 at 7:51 Michel 4,15744 gold badges3737 silver badges5656 bronze badges asked Jun 13, 2016 at 13:16 BorjaBorja 3,57977 gold badges3838 silver badges7575 bronze badges 7

• 8 keydown event occures before the value is updating, use keyup or input event instead – Pranav C Balan Commented Jun 13, 2016 at 13:17
• Use console.log to debug, not alert – j08691 Commented Jun 13, 2016 at 13:18
• @PranavCBalan how kind of form event ? maybe change() ? – Borja Commented Jun 13, 2016 at 13:19
• @Borja : which fires when you leave focus in case of text field – Pranav C Balan Commented Jun 13, 2016 at 13:20
• 1 @PranavCBalan ok thanks a lot for the suggest ;) – Borja Commented Jun 13, 2016 at 13:21

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3 Answers 3

Sorted by: Reset to default 3

Use keuyp event:

This is because keypress events are fired before the new character is added to the value of the element (so the first keypress event is fired before the first character is added, while the value is still empty). You should use keyup instead, which is fired after the character has been added.

$('#search-vulc').on('keyup', function() {
  var textinsert = ($(this).val()).toLowerCase();
  alert(textinsert);
});

Use keyup instead:

$('#search-vulc').on('keyup', function() {

  var textinsert = ($(this).val()).toLowerCase();
  alert(textinsert);

});

<script src="https://ajax.googleapis./ajax/libs/jquery/2.1.0/jquery.min.js"></script>

<input type="text" size="150" style="width: 150px;" name="qu" id="search-vulc">

Updated fiddle: https://jsfiddle/06xg4c78/2/

if you use keydown functions it works before dom gets the input value

Use keyup which fires the event when you leave the key so it will get the value entered

$('#search-vulc').on('keyup', function() {
  var textinsert = ($(this).val()).toLowerCase();
  alert(textinsert);
});

<script src="https://ajax.googleapis./ajax/libs/jquery/2.1.0/jquery.min.js"></script>
<input type="text" size="150" style="width: 150px;" name="qu" id="search-vulc">

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