POSTing an array of n items to form

Question

POSTing an array of n items to form

I'd like to post an array of n length to a form. What's the best way to handle this?

The object is a Timesheet, which has a date, and an array of Lines.

Lines have a duration, category, and note field.

My form has a date field, and one line to start, and jQuery appends more lines as necessary.

I know I need to use bracket notation somehow, but I don't know how considering I have two objects nested.

FWIW, the application end of things is in Node.js and express.

<form id="timesheet" method="POST" action="/timesheets">
  <label>date for timesheet</label>
  <input type="date" name="date"/><br/>
  <ol id="timesheet-list">
    <li>
      <input type="number" name="hours" min="0" value="0" step=".25"/>
      <input type="text" name="category"/>
      <input type="text" name="details"/>
    </li>
  </ol>
  <input type="submit"/>
</form>

<a id="addItem" href="#">Add a new line item</a>

<script type="text/javascript">
  $('#addItem').click(function(e){
    e.preventDefault();
    $('#timesheet-list').append('<li><input type="number"> <input type="text"> <input type="text"></li>');
  });
</script>

javascript
html
forms
node.js

Answer 1

You want to format you data in JSON to POST to your form?

Your JSON object would look something like this.

// Entire object is a representation of a 'Timesheet'
{
  date: '8-8-2012',
  lines: [ // Array of objects, each storing a duration, catagory and note.
    {
      duration: 0,
      catagory: 'whatever',
      note: 'whatever'
    },
    { // Have as many of these as you please.
      duration: 123,
      catagory: 'another',
      note: 'moar notes'
    },
  ]
}

When you receive this object, you can access the data like so:

data = getTimesheet(); // Assume this function gets the above JSON
data.date;
for(var i=0; i<data.lines.length; i++) {
    data.lines[i].duration;
    data.lines[i].catagory;
    data.lines[i].note;
}

Answer 2

I think you could serialize your input values if you want to submit it as a JSON data using the jQuery serializeArray method

      $('form').submit(function() {
          alert($(this).serializeArray());
          return false;
      });

NOTE that for the above to work your <input ...> must have a name attribute.

For others who may be looking to encode more complex data (object types) into form-data this answer here is helpful. Basically, it uses the serializeArray function to turn it into a JavaScript object (following code is included because the link may go inactive over time)

  $.fn.serializeObject = function()
  {
   var o = {};
   var a = this.serializeArray();
    $.each(a, function() {
       if (o[this.name] !== undefined) { //check to see if name attribute exists
           if (!o[this.name].push) { 
              o[this.name] = [o[this.name]];
           }
           o[this.name].push(this.value || '');
         } else {
            o[this.name] = this.value || ''; 
          }
    });
    return o;
 };

Using the function

 $(function() {
     $('form').submit(function() {
         $('#result').text(JSON.stringify($('form').serializeObject()));
      return false;
    });
});