Question

I have a php command that like this.

  $query = "SELECT * FROM $table WHERE user_id = 0";
  $results = mysql_query($query)or die(mysql_error());
  while($row = mysql_fetch_assoc($results)){

  $values []= $row;

  }
  echo json_encode($values);

This creates a json array like this

[{"id":"1","name":"amazon.com","url":"http:\/\/amazon.com","time":"5","credits":"0","user_id":"0"},{"id":"2","name":"google.com","url":"http:\/\/google.com","time":"4","credits":"0","user_id":"0"}]

This json array than becomes part of a ajax response Text on a different page.

   var ajaxd = ajax();
        ajaxd.onreadystatechange = function(){

        if(ajaxd.readyState == 4){
         var nse = eval('('+ajaxd.responseText+')');
          alert(nse['url']);
        }
      }

The problem is.. The alert is always being undefined. What am I doing wrong?

Answer 1

the outermost containing structure in the resulting json is a list; this makes sense because most data returned from a database will be a bunch of rows. You probably want to access the ‘url’ of the first row:

nse[0]["url"]

Or maybe you really need to do something with every row:

for (i = 0; i < nse.length(); ++i)
{
    row = nse[i];
    alert(row['url']);
}