In some websites, sometimes we need to do some operations when closing the web page, such as reminding the user to save data, or recording certain operations of the user on the web page, etc. These operations need to be automatically triggered when the user closes the web page, and jquery provides several methods to determine the event of closing the window.
1. beforeunload event
The beforeunload event is an event triggered when a window, document, or frame is unloaded or closed. This event will be triggered before the actual uninstall or shutdown. A prompt box can pop up in this event to prompt the user to save data or other operations.
The code is as follows:
$(window).on('beforeunload', function() { return 'Are you sure you want to leave?'; });
In this code, the beforeunload event is bound to the window object. When the user closes or leaves the page, a prompt box will pop up asking the user if they are sure they want to leave. The user can choose to stay or close the window.
2. Unload event
The unload event is an event triggered when a window, document, or frame is unloaded or closed. This event will be triggered after the web page is unloaded or closed. Certain operations of the user on the web page can be recorded in this event.
The code is as follows:
$(window).on('unload', function() { // 记录用户离开时间 var leaveTime = new Date(); localStorage.setItem('leaveTime', leaveTime.getTime()); });
In this code, the unload event is bound to the window object. When the user closes or leaves the page, the time the user left the page is recorded and saved in localStorage.
3. You can use the beforeunload and unload events at the same time
The code is as follows:
$(window).on('beforeunload', function() { // 提醒用户保存数据 return 'Are you sure you want to leave?'; }); $(window).on('unload', function() { // 记录用户离开时间 var leaveTime = new Date(); localStorage.setItem('leaveTime', leaveTime.getTime()); });
In this code, the beforeunload and unload events are bound at the same time. When the user closes or leaves the page, a prompt box will pop up asking the user if they are sure they want to leave. The user can choose to stay or close the window, and then the time when the user leaves the page will be recorded and saved in localStorage.
Summary
When you need to do some operations on a web page when the user closes or leaves the page, you can use the beforeunload and unload events. Among them, the beforeunload event is triggered before the web page is actually closed, and a prompt box can pop up in this event; the unload event is triggered after the web page is closed, and the user's operations can be recorded in this event. At the same time, these two events can be used at the same time to implement multiple operations.
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