I have a registration form on my website and I use jQuery's AJAX function to send the data into my ASP.NET API.
My AJAX looks like this:
$.ajax({
type: "POST",
url: '[urlHere]',
data: {
'Name': userName,
'LastName': userLastName,
'Email': userEmail,
'Password': userPass
},
dataType: 'application/json',
success: function (response) {
console.log('Success');
},
error: function (err) {
console.log('Error');
}
});
(The values in the data object are values I got from the inputs on my website)
The data I send into the API gets inserted into a SQL Database Table. Running this AJAX function successfully inserts my data into my Database, but it always runs the error function. I have tested the API in apps like Postman, and the API works perfect, but my AJAX always runs error. When I console.log the error that gets returned, it returns the statusCode of OK, which is what I set it to if everything goes successfully in the API.
jQuery tends to call the error function for successful responses when it cannot parse the response to the desired data type. First of all, I don't believe application/json is a proper value for the dataType property. Change it to just json first. If that doesn't work, remove that line completely, log the response and verify whether your response is in fact a proper JSON.
Reference: jQuery Ajax Data Types
Set these codes in your ajax :
contentType: 'application/json; charset=utf-8',
processData: false,
Related
Issue:
The first ajax is working properly in the main.js, the second one is doing its job at first look but I think there might be a bug somewhere. I can reach the getProducts method after I click to the button.
The product_list.html file should appear on the browser screen, but it doesn't.
I get no error message on the front-end or the back-end.
This is what I noticed: After click to the button -> F12 -> Network -> products -> I can see here a status code: 200 and the product_list.html file content as response.
In case the POST ajax call succeeds and in the case I add: location.href = "/products";, the browser will load product_list.html
I use the get ajax call because i need to pass the jwt token in the req header. (I deleted the jwt authentication parts from the code below because I narrowed down the error to the $.ajax() and res.sendFile() relationship)
//routes.js
routes.get("/products", ProductController.getProducts);
//ProductController.js
var root = path.join(__dirname, '../../views');
module.exports = {
getProducts(req, res){
console.log("getProducts!"); //I can see in the console
res.sendFile("product_list.html", {root}) //It doesn't render the html
},
}
//main.js
$("#btn-login").click(function(){
$.ajax({
type: 'POST',
url: "http://localhost:8000/login",
dataType: "json",
contentType: "application/json",
data: JSON.stringify({
"username": $("#login-user").val(),
"password": $("#login-pwd").val(),
}),
success: function(data){
if ($("#login-chkbx").is(':checked')){
$.ajax({
url: "http://localhost:8000/products",
type: 'GET',
beforeSend: function (xhr) {
xhr.setRequestHeader("user", localStorage.getItem("user"));
},
});
}
}else{
console.log("Checkbox is not checked");
}
}
});
});
What causes the issue and how to solve it?
Thanks!
file should appear on the browser screen
No it does not and it should not. The file should be returned to the ajax function call in the success callback:
$.ajax({
url: "http://localhost:8000/products",
type: 'GET',
beforeSend: function (xhr) {
xhr.setRequestHeader("user", localStorage.getItem("user"));
},
success: function (file) {
// The file is in the "file" variable above.
// Do whatever you want with it. For example you can replace
// the current page with the returned file:
document.body.innerHTML = file;
}
});
That is the whole point of AJAX - a mechanism for programmers to override the normal flow of HTTP requests that loads the response to the browser page. If it allows you to not load the response to the browser page it also means it will not automatically load the response to the browser page - because doing so will not allow you to not load the response.
If you want to automatically load the response then don't use ajax:
// Replace $.ajax(... with:
window.location.href = "http://localhost:8000/products";
However, this method does not allow you to set custom request header.
in your frontend code you do nothing with the GET /products response
the backend sendfile as the name says it just sends the file over to the requester. Being an ajax call, it must be rendered by the frontend code.
Add something like success: response => $('body').html(response)
I am building a web app that displays data about flowers that is stored in my local server running bottle.
My front end is html, js with ajax;
My back end is python with bottle
In the browser there is an empty div in which the data is to be displayed.
Below it there is a row of images. When the user clicks on an image the data should display in the div above.
I tried using $.ajax instead of $.get, and I'm getting the same result.
This is my event listener in js:
$('.image').click((e)=>{
$('.selected').removeClass('selected');
$(e.target).addClass('selected'); // just a visual indication
$.get('/flowerdesc/'+$(e.target).attr('id')).done((data)=>{
flowerInfo = JSON.parse(data);
$('#flower-title').empty();
$('#flower-title').html(flowerInfo.name);
$('.desc-text').empty();
$('.desc-text').html(flowerInfo.description);
})
})
This is my handler for this request:
#get('/flowerdesc/<flower>')
def get_flower_desc(flower):
return json.dumps(data[data.index(filter(lambda f: f.name == flower, data)[0])])
(data is an array of dictionaries, each containing data of a single flower)
I am getting a 404 error (the function get_flower_desc is not executed at all) that possibly is happening because of the argument, because whenever I use a a function with no parameters and pass in no arguments I am getting the result that I'm expecting.
I found that I had to formulate an AJAX request quite precisely to get it to work well with Bottle in a similar scenario.
Here is an example with a GET request. You could attach this function to the event handler or move it directly to the event handler.
function getFlowerData(id) {
$.ajax({
type: "GET",
cache: false,
url: "/flowerdesc/" + id,
dataType: "json", // This is the expected return type of the data from Bottle
success: function(data, status, xhr) {
$('#flower-title').html(data['name']);
$('.desc-text').html(data['description']);
},
error: function(xhr, status, error) {
alert(error);
}
});
};
However, I found better results using a POST request from AJAX instead.
function getFlowerData(id) {
$.ajax({
type: "POST",
cache: false,
url: "/flowerdesc",
data: JSON.stringify({
"id": id,
}),
contentType: "application/json",
dataType: "json",
success: function(data, status, xhr){
$('#flower-title').html(data['name']);
$('.desc-text').html(data['description']);
},
error: function(xhr, status, error) {
alert(error);
}
});
};
For the POST request, the backend in Bottle should look like this.
#post("/flowerdesc") # Note URL component not needed as it is a POST request
def getFlowerData():
id = request.json["id"]
# You database code using id variable
return your_data # JSON
Make sure your data is valid JSON and that the database code you have is working correctly.
These solutions using AJAX with Bottle worked well for me.
I want to make a post request to an API (http://nairabox.com/food_documentation/) using Ajax but am kind of confused on how to go about it.
This is what I have tried so far:
$.ajax({
type: "POST",
url: "https://mapp.nairabox.com:8443/api/v1/food/",
dataType : "json",
data: { case: "browse"},
headers: {
'case': 'browse'
},
success: function(data){
console.log('success');
}
})
So far, it is returning no result.
What could I be getting wrong?
The API doc is here (http://nairabox.com/food_documentation/)
The documentation you link to does not say to add any custom HTTP request headers.
You, however, are doing so here:
headers: {
'case': 'browse'
},
The case data belongs in the data and only in the data.
By adding the custom header, you are preventing the request from being simple and triggering a preflight OPTIONS request which the server does not accept.
Remove the above and you will get a response (and your success function will fire … you should probably do something with the data argument though)
Note, also, that the documentation says you should pass latitude and longitude as well as case.
Unless you add them, the response you get is unlikely to be useful.
My Code is as below for Javascript
$.ajax({
type: "POST",
url: "page/rSales.aspx",
data: { ListID: '1', ItemName: 'test' },
dataType: "json",
success: function (res) {
alert('Success');
},
error: function (res) {
alert('Fail');
}
});
I use http tracer tools to trace whether or not the parameter is passing on to my backend - and it is not. I have also tried adding contentType: 'application/json; charset=utf-8', adjust parameter by adding colon, but none of it is working.
My Backend code C# :
Request.Params["ListID"].ToString();
It always returns null, due to the parameter not passing on. I am wondering what is causing this problem and how should I resolve it.
The Request.Params collection does not support JSON requests, so you have to parse response body manually (or send it as form data).
https://msdn.microsoft.com/en-us/library/system.web.httprequest.params(v=vs.110).aspx says "Gets a combined collection of QueryString, Form, Cookies, and ServerVariables items."
For firefox you declare var event; before your ajax call this is very well known issue in firefox.
i am using jquery with ASP.net MVC (backend doesn`t really matter i think)
in javascript, i have a helper function like this
postAsync: function (url, data) {
return $.ajax({
url: url,
data: JSON.stringify(data),
type: 'POST',
contentType: 'application/json; charset=utf-8',
dataType: 'json'
});
}
and when i want to interact with server, i will do
postAsync("/mycontroler/methodname", {input: value}).done(function(){
// show success message
}).fail(function(err){
// show error message
});
however, all my ajax request always end up in "fail" callback.
i look into the "err" object, i can see
status: 200
statusText: "OK"
but why it is end up in error. i debug my controller, it is just fine!!! no exception at all.
any idea?
If your server does not give you json, the status is actually 200/OK but jquery cannot parse json and so it fails. Or it might be an empty answer which is considered as an invalid json content since jQuery 1.9 : http://jquery.com/upgrade-guide/1.9/#jquery-ajax-returning-a-json-result-of-an-empty-string – Zzirconium 15 mins ago
return an empty object resolve the issue