js implements reminder of unsaved information when leaving the page (reduces user repeated operations)_javascript skills

Javascript code

Copy code The code is as follows:

//Leave Determine whether there are unsaved input values ​​when page
var hasSaved = false;//Whether there is an unsaved flag for input content, the initial value is false
function CheckUnsave(){
if(hasSaved==false ){
alert("What you uploaded has not been saved, please save it before leaving the page");
return false;}
//return true; //This statement cannot be added
}

//Change the state after saving
function ChangeState()
{
hasSaved = true;
}

Add the attribute onbeforeunload to the body
Html code

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Call ChangeState before submitting the action.
If you press a certain button and leave the page, you will no longer be reminded. For example, if you press the save button, you need to modify the status of the save identifier after pressing the save button:
Html code

Copy code The code is as follows: