Question

Hi I have this ajax script:

function updatePage() {   
if (request.readyState == 4) {   
    if (request.status == 200)
        // get response array
        var data = JSON.parse(request.responseText); 
        update_select($('select[name=island_name]'), data);
    }
    else if (request.status == 404) {
        alert("Request url does not exist");
    }
    else {
        alert("Error: status code is " + request.status);
    }
}  

The script executes fine but when it does I get an alert with ‘Error: status code is 200`. Why is the script entering this else block when the status is 200? What Can I do to prevent this?

Answer 1

The if (request.status == 200) condition has no {.
Therefore, its effect is just one line, and the chain of elses apply to the outer if.

If you indent it correctly, your code looks like this:

function updatePage() {
    if (request.readyState == 4) {
        if (request.status == 200) 
            var data = JSON.parse(request.responseText);
        update_select($('select[name=island_name]'), data);
    } else if (request.status == 404) {
        alert("Request url does not exist");
    } else {
        alert("Error: status code is " + request.status);
    }
}