Autosave input box's to database during pause

问题:

I have a large form on my website that I want to be able to autosave to a database as the user is filling it out. Almost identical to how google drive works when typing a document.

I am trying not to have a function that runs every X seconds but rather a function that runs when the user has taken a break in typing. So, if the user has not typed in 1 hour but is still on the page, it doesn't keep pushing save requests.

This is all I have so far which is a basic javascript form submit.

$("#page1Form").submit(function(event){
  event.preventDefault();  
  $changesSaved.text("Saving...");
  var url = "/backend/forms/page1-POST.php";
        $.ajax({
         type: "POST",
         url: url,
         data: $("#page1Form").serialize(),
         success: function(data) { $changesSaved.text(data); }
        });
  return false;
  });

回答1:

Debounce the textarea change.

Demo: jsFiddle

Put your ajax call in the saveToDB() function. These event names('input propertychange change') will trigger on any form element change such as radio buttons, inputs, etc.

var timeoutId;
$('#the-textarea').on('input propertychange change', function() {
    console.log('Textarea Change');

    clearTimeout(timeoutId);
    timeoutId = setTimeout(function() {
        // Runs 1 second (1000 ms) after the last change    
        saveToDB();
    }, 1000);
});

function saveToDB()
{
    console.log('Saving to the db');    
}

---

Here is a full demo showing you how to debounce a full form and use ajax to send the data and then return the status (Saving, Saved, etc).

Demo full form and ajax: jsFiddle

回答2:

I know that this question is old, but I would like to include a code that I like the most. I found it here: http://codetunnel.io/how-to-implement-autosave-in-your-web-app/

Here is the code:

var $status = $('#status'),
    $commentBox = $('#commentBox'),
    timeoutId;

$commentBox.keypress(function () {
    $status.attr('class', 'pending').text('changes pending');

    // If a timer was already started, clear it.
    if (timeoutId) clearTimeout(timeoutId);

    // Set timer that will save comment when it fires.
    timeoutId = setTimeout(function () {
        // Make ajax call to save data.
        $status.attr('class', 'saved').text('changes saved');
    }, 750);
});

It saves after the user stops writing for more than 750 milliseconds.

It also has a status letting the user know that the changes have been saved or not.

回答3:

Try Sisyphus.js https://github.com/simsalabim/sisyphus. It persists the form data in the browser's local storage and is robust against tabs closing, browser crashes, etc...