Ajax请求POST错误

I have some problems with request to file. I have to edit the data in the table created in the plugin. When I click on the text, I create an input. I change the data and when I press the enter key this data should be sent to the update_cell.php file but when I output it for example echo $ _POST ["id "] I get the error Notice:

Undefined index: id in W: \ domains \ test \ wp-content \ plugins \ related-equipment \ includes \ update_cell.php on line 2

Is it possible my path is incorrectly specified? Although I propps it as absolute. I think problems should not be

jQuery(document).ready(function($){
$('td.edit').click(function(){
$('.ajax').html($('.ajax input').val());
$('.ajax').removeClass('ajax');
$(this).addClass('ajax');
$(this).html('<input id="editbox" size="'+ $(this).text().length+'" type="text" value="' + $(this).text() + '" />');
$('#editbox').focus();
});

//UPDATE TABLE
$('td.edit').keydown(function(event){
eq_arr = $(this).attr('class').split( " " );
   if(event.which == 13)
   {
var table = $('table').attr('id');
 $.ajax({ type: "POST",
 url:"http://test/wp-content/plugins/related-equipment/includes/update_cell.php",
 data: "value="+jQuery('.ajax input').val()+"&id="+eq_arr[1]+"&field="+eq_arr[2]+"&table=gc-equip",
 success: function(data){
     console.log(this);
 $('.ajax').html($('.ajax input').val());
 $('.ajax').removeClass('ajax');
 }});
 }});

 $(document).on('blur', '#editbox', function(){
$('.ajax').html($('.ajax input').val());
$('.ajax').removeClass('ajax');
});
});

You need to pass data like this with post method :

data : {
    value: jQuery('.ajax input').val(),
    id: eq_arr[1],
    field: eq_arr[2]
    // and so on
}

Then after you can get the values at server side using $_POST[key] here key will be value, id, field that you passed via ajax