Ajax发布方法错误

Question

In the following example I am able to pass JSON representation of the country list and display it but I cannot display the message "Could not find any countries". Could you please check the code below:

Controller:

if ($this->model_abc->did_get_country_list($user_id)) {             
        $country["results"]= $this->model_abc->did_get_country_list($user_id);          
            echo json_encode($country);         
        }
        else {      
        $country = array('message' => "Could not find any countries" );
            echo json_encode($country);     
        }

JS file:

$.post('cont/get_country_list', function (country) {
    $.each(country.results, function(i, res) {
        var item = $('<div>'),               
        title = $('<h3>');
        title.text(res);
        item.append(title);
        item.appendTo($("#country_list_is_got"));
    });   
}, 
       "json").error(function() { 
           $( "#country_list_is_not_got").text(country.message);
       });

Update:

I changed my code as following and now I get thise error from console: Uncaught TypeError: Cannot read property 'length' of undefined.

JS file:

$.post('cont/get_country_list', function (country) {
    if (country.message !== undefined) {
        $( "#country_list_is_not_got").text(country.message);
    } else {
        $.each(country.results, function(i, res) {
             var item = $('<div>'),               
                 title = $('<h3>');
                 title.text(res);
                 item.append(title);
                 item.appendTo($("#country_list_is_got"));
        });  


 }
});

Answer 1

You're not setting an error reply code in the case where no countries are found, so it's not treated as an error by jQuery.

else {
    header("HTTP/1.1 500 Error");
    $country = array('message' => "Could not find any countries" );
    echo json_encode($country);
}

Also, your error function needs to get the data from its parameter:

.error(function(xhr) {
    country = $.parseJSON(xhr.responseText);
    $( "#country_list_is_not_got").text(country.message);
});