Problem displaying error to the user from AJAX - html

Question

Am using AJAX code whereby I handle errors form the backend code.. All is working well except that I want to alert the errors individually to the user in a numbered list
Expected Output
1. Please insert a valid phone number
2. Please insert your email
3. Please insert a valid passport number
AJAX code handling errors
error: function(data) {
//Unblock the spinner
$.unblockUI();
var errors = '';
for(datos in data.responseJSON){
errors += data.responseJSON[datos] + '<br>';
}
//Alert each error individually
alert(errors);
}

Answer 1

I would recommended that you should be using a for loop instead of for in. See why here
error: function(data) {
//Unblock the spinner
$.unblockUI();
var errors = '';
for(var i = 0; i < data.responseJSON.length; i++){
// Remove the "(i+1) + '. ' + " if your json response already contains that part.
errors += (i+1) + '. ' + data.responseJSON[i] + '\n'; // <-- Notice how the br tag is changed to a new line
}
alert(errors)
}
I also changed the <br> tag to a \n as alerts don't support html tags.

Answer 2

It is not clear to me from the question, whether you want a
multiline alert message or
multiple alert dialogs as the
output,
but in case 1) is true, you should use newline ("\n") instead of br tag - see New line in JavaScript alert box and the code could look like:
var i = 1,
errors = '';
for(datos in data.responseJSON){
errors += i + '. ' + data.responseJSON[datos] + '\n';
i++;
}
//Alert each error individually
alert(errors);
If 2) is what you need, you should call alert() for each error message