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目录

onfocus Event

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Example

Call a function when an input field gets focus:

<input type="text" onfocus="myFunction()">
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Description

The onfocus event occurs when an element gets focus.

The onfocus event is often used on input fields.

Focus Based Events

Event Occurs When
focus An element gets focus
blur An element loses focus
focusin An element gets focus
focusout An element loses focus

See Also:

The Focus Event Object

Syntax

In HTML:

< element onfocus=" myScript">
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In JavaScript:

object.onfocus = function(){ myScript};
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In JavaScript, using the addEventListener() method:

object.addEventListener("focus", myScript);
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Technical Details

Bubbles: No
Cancelable: No
Event type: FocusEvent
HTML tags: ALL HTML elements, EXCEPT: <base>, <bdo>, <br>, <head>, <html>, <iframe>, <meta>, <param>, <script>, <style>, and <title>
DOM Version: Level 2 Events

Browser Support

onfocus is a DOM Level 2 (2001) feature.

It is fully supported in all browsers:

Chrome Edge Firefox Safari Opera IE
Yes Yes Yes Yes Yes 9-11

More Examples

Example

Using onfocus and onblur:

<input type="text" onfocus="focusFunction()" onblur="blurFunction()">
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Example

Clear input field on focus:

<input type="text" onfocus="this.value=''" value="Blabla">
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Example

Event delegation: using focus and blur events:

Set useCapture parameter of addEventListener() to true:

<form id="myForm">
  <input type="text" id="myInput">
</form>

<script>
let x = document.getElementById("myForm");
x.addEventListener("focus", myFocusFunction, true);
x.addEventListener("blur", myBlurFunction, true);

function myFocusFunction() {
  document.getElementById("myInput").style.backgroundColor = "yellow";
}

function myBlurFunction() {
  document.getElementById("myInput").style.backgroundColor = "";
}
</script>
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Example

Event delegation: using focusin and focusout events:

<form id="myForm">
  <input type="text" id="myInput">
</form>

<script>
let x = document.getElementById("myForm");
x.addEventListener("focusin", myFocusFunction);
x.addEventListener("focusout", myBlurFunction);

function myFocusFunction() {
  document.getElementById("myInput").style.backgroundColor = "yellow";
}

function myBlurFunction() {
  document.getElementById("myInput").style.backgroundColor = "";
}
</script>
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