Obtaining Dropdown Value Before Change
In jQuery, the change event is often used to capture the value of a
One solution involves combining the focus and change events. When the dropdown receives focus, the current value can be stored in a variable. When the change event occurs, this stored value can be used to determine the value before the change.
Here's how you can implement this solution:
(function () {
var previous;
$("select").on('focus', function () {
// Store the current value on focus and on change
previous = this.value;
}).change(function() {
// Do something with the previous value after the change
alert(previous);
// Make sure the previous value is updated
previous = this.value;
});
})();
In this script:
- The focus event listener stores the current value of the dropdown in the previous variable.
- The change event listener executes an action that utilizes the previous value, such as displaying it in an alert box.
- The previous variable is then updated to the new value of the dropdown.
This approach allows you to capture the value of the dropdown before it changes. Keep in mind that this technique should be applied to all
A live example of this solution can be found at the following URL: http://jsfiddle.net/x5PKf/766.
The above is the detailed content of How to Get the Value of a Dropdown Before It Changes in jQuery?. For more information, please follow other related articles on the PHP Chinese website!
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