I want to check if a page returns the status code 401. Is this possible?

Here is my try, but it only returns 0.

$.ajax({
    url: "http://my-ip/test/test.php",
    data: {},
    complete: fun开发者_运维问答ction(xhr, statusText){
    alert(xhr.status); 
    }
});

this is possible with jQuery $.ajax() method

$.ajax(serverUrl, {
   type: OutageViewModel.Id() == 0 ? "POST" : "PUT",
   data: dataToSave,
   statusCode: {
      200: function (response) {
         alert('1');
         AfterSavedAll();
      },
      201: function (response) {
         alert('1');
         AfterSavedAll();
      },
      400: function (response) {
         alert('1');
         bootbox.alert('<span style="color:Red;">Error While Saving Outage Entry Please Check</span>', function () { });
      },
      404: function (response) {
         alert('1');
         bootbox.alert('<span style="color:Red;">Error While Saving Outage Entry Please Check</span>', function () { });
      }
   }, success: function () {
      alert('1');
   },
});

The third argument is the XMLHttpRequest object, so you can do whatever you want.

$.ajax({
  url  : 'http://example.com',
  type : 'post',
  data : 'a=b'
}).done(function(data, statusText, xhr){
  var status = xhr.status;                //200
  var head = xhr.getAllResponseHeaders(); //Detail header info
});

Use the error callback.

For example:

jQuery.ajax({'url': '/this_is_not_found', data: {}, error: function(xhr, status) {
    alert(xhr.status); }
});

Will alert 404

I think you should also implement the error function of the $.ajax method.

error(XMLHttpRequest, textStatus, errorThrown)Function

A function to be called if the request fails. The function is passed three arguments: The XMLHttpRequest object, a string describing the type of error that occurred and an optional exception object, if one occurred. Possible values for the second argument (besides null) are "timeout", "error", "notmodified" and "parsererror".

$.ajax({
    url: "http://my-ip/test/test.php",
    data: {},
    complete: function(xhr, statusText){
        alert(xhr.status); 
    },
    error: function(xhr, statusText, err){
        alert("Error:" + xhr.status); 
    }
});

I found this solution where you can simply, check the server response code using status code.

Example :

$.ajax({
type : "POST",
url : "/package/callApi/createUser",
data : JSON.stringify(data),
contentType: "application/json; charset=UTF-8",
success: function (response) {  
    alert("Account created");
},
statusCode: {
    403: function() {
       // Only if your server returns a 403 status code can it come in this block. :-)
        alert("Username already exist");
    }
},
error: function (e) {
    alert("Server error - " + e);
} 
});

$.ajax({
    url: "http://my-ip/test/test.php",
    data: {},
    error: function(xhr, statusText, errorThrown){alert(xhr.status);}
});

I encapsulate the jQuery Ajax to a method:

var http_util = function (type, url, params, success_handler, error_handler, base_url) {

    if(base_url) {
        url = base_url + url;
    }

    var success = arguments[3]?arguments[3]:function(){};
    var error = arguments[4]?arguments[4]:function(){};



    $.ajax({
        type: type,
        url: url,
        dataType: 'json',
        data: params,
        success: function (data, textStatus, xhr) {

            if(textStatus === 'success'){
                success(xhr.code, data);   // there returns the status code
            }
        },
        error: function (xhr, error_text, statusText) {

            error(xhr.code, xhr);  // there returns the status code
        }
    })

}

Usage:

http_util('get', 'http://localhost:8000/user/list/', null, function (status_code, data) {
    console(status_code, data)
}, function(status_code, err){
    console(status_code, err)
})

I have had major issues with ajax + jQuery v3 getting both the response status code and data from JSON APIs. jQuery.ajax only decodes JSON data if the status is a successful one, and it also swaps around the ordering of the callback parameters depending on the status code. Ugghhh.

The best way to combat this is to call the .always chain method and do a bit of cleaning up. Here is my code.

$.ajax({
        ...
    }).always(function(data, textStatus, xhr) {
        var responseCode = null;
        if (textStatus === "error") {
            // data variable is actually xhr
            responseCode = data.status;
            if (data.responseText) {
                try {
                    data = JSON.parse(data.responseText);
                } catch (e) {
                    // Ignore
                }
            }
        } else {
            responseCode = xhr.status;
        }

        console.log("Response code", responseCode);
        console.log("JSON Data", data);
    });