Undefined parameter when returning data from jQuery.post to PHP

Question

I am trying to return data from a database and populate a text field after the user enters an ID in the first text box. Currently I had the code working as long as the user did not enter a space in the ID number. Now I am attempting to allow that use case. My PHP code returns a json encoded array with three fields: first_name, last_name, and full_name.

When I use console.log(data) to view the data being returned I receive the following:

    {"first_name":"Test","last_name":"Test","full_name":"Test Test"}

However in my code, I try to write data.full_name in a .val() nothing is populated, and when use the console.log I get an error saying "undefined".

Here is the whole jQuery Code:

    $("#ID").blur(function () {
        var params = {};
        params.ID = encodeURIComponent($(this).val());
        $.post("getter.php", params, function ( data ) {
          if (!data) {
             $("input[name=username]").val("User Not Found");
          } else {
             $("input[name=username]").val(data.full_name);
             $("input[name=username]").attr("readonly", true);
          }
        });
     });

Any help you can offer would be much appreciated.

themerlinproject · Accepted Answer · 2014-04-22 02:38:01Z

1

Force jQuery to read the returned data as json:

$("#ID").blur(function () {
        var params = {};
        params.ID = encodeURIComponent($(this).val());
        $.post("getter.php", params, function ( data ) {
          if (!data) {
             $("input[name=username]").val("User Not Found");
          } else {
             $("input[name=username]").val(data.full_name);
             $("input[name=username]").attr("readonly", true);
          }
        }, "json"); // <- json forced
     });

and then make sure your returned data is in proper json format (for example with json_encode in php)

answered Apr 22, 2014 at 2:38

themerlinproject

3,5825 gold badges40 silver badges55 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

dooms13 Over a year ago

By adding JSON to the post, it will send the data to the PHP page as a JSON object, correct? How can I pull that information to run my SQL query on the getter page? Sorry, that is a new method to me.

themerlinproject Over a year ago

No, it will interpret the data you are getting back as a json object. This is why you are not able to use data.full_name with your above code - jquery is not interpreting the data it receives back as an object. See the jquery documentation on $.post: api.jquery.com/jQuery.post .

Loïc · Accepted Answer · 2014-04-22 02:29:08Z

0

Use trim() to remove spaces.

Then you can check if the parameter value is_numeric(), and if false, set a default value.

answered Apr 22, 2014 at 2:29

Loïc

12k2 gold badges35 silver badges52 bronze badges

Collectives™ on Stack Overflow

Undefined parameter when returning data from jQuery.post to PHP

2 Answers 2

2 Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

2 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related