jquery has focus() method. When an element gains focus, a focus event occurs; in jquery, you can use the focus() method to trigger the focus event, or specify an event handling function to be run when a focus event occurs, with the syntax "$(selector).focus()" or " $(selector).focus(function)".
The operating environment of this tutorial: windows7 system, jquery3.6 version, Dell G3 computer.
jquery has the focus() method, which is used to trigger the focus event or specify the processing function of the focus event.
What is focus
Focus is the area of focus, that is, the position where the cursor is currently activated, the small vertical flashing in the page screen Line indicates that a control on the web page is selected and can be operated. Click the mouse to get the cursor, and the Tab key can switch focus according to the set Tabindex.
For example, if a text box gets the focus, the characters you type on the keyboard will directly enter the text box; or if a drop-down list box gets the focus, if you press the down arrow on the keyboard, it will A list will be made. The program also has events that occur when focus is gained (gotfocus()), events that occur when focus is lost (lostfocus()), and a method to set focus for the control (setfocus()). Making good use of focus can make your program appear very user-friendly.
jquery focus() method
When an element gets focus, the focus event occurs.
When an element is selected by mouse click or positioned by tab key, the element will gain focus.
The focus() method triggers the focus event, or specifies a function to run when the focus event occurs.
Syntax:
//触发 focus 事件 $(selector).focus() //将函数绑定到 focus 事件 $(selector).focus(function)
function: Optional. Specifies the function to be run when the focus event occurs.
Example: focus() method gets focus
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<script ></script>
<script>
$(document).ready(function(){
$("input").focus(function(){
$("input").css("background-color","#FFFFCC");
});
});
</script>
</head>
<body>
输入你的名字: <input type="text">
</body>
</html>
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