I've been a PHP developer for a few years now and have developed at least a dozen APIs using JSON. Create a url that does a task, and return json_encode($array)... Piece of cake...right?
Now, I used to be a .net developer a while back (about 8 yrs ago) and I've been given the task to develop a small api/webservice for a client. I've been doing some reading on WCF and have been tinkering with it for a few hours now. My question is.. Is it me or is it incredibly over complicated to just run a RESTFUL query and return a block of JSON? In other words, why can't I just create an ASPX page that takes an array and encodes it as JSON and spits it out? Does it really HAVE to be WCF? Or even ASMX for that matter? Feels like overkill? No? Can someone offer a valid reson on why I need to go through the pain of WCF if I'm making a simple service that returns a few lines of JSON?
You can use WebMethods:
Using jQuery to directly call ASP.NET AJAX page methods
Code-behind:
public partial class _Default : Page
{
[WebMethod]
public static string GetDate()
{
return DateTime.Now.ToString();
}
}
Script:
$.ajax({
type: "POST",
url: "Default.aspx/GetDate",
data: "{}",
contentType: "application/json; charset=utf-8",
dataType: "json",
success: function(msg) {
// alert(msg.d);
}
});
Related
My requirements - I have a web api whch gives me all data from db. I have a .net website which consumes this api to get all data. Now what I want is when I'm login my website I want to manage session in "API".
I know session in web api is not a good approach but still I need to do this.
I have already implemented session management in web api(taken reference from here) and its working fine if I'm sending all my request from postman(i.e. I'm setting variables in session by calling 1 method and retrieving that session variable by calling 2nd method). But when I'm doing the same from asp.net website with jQuery then I'm not getting stored session variable(what I noticed is I'm getting session id different every time-for each request).
code of saving variable in session
$.ajax({
url: 'http://localhost:63726/api/Login/Login',
type: "GET",
dataType: "JSON",
success: function (data) {
alert("success");
},
error: function (data) {
alert("error");
}
});
code of retrieving variable stored in session
$.ajax({
url: 'http://localhost:63726/api/SessionCheck/LoginName',
type: "GET",
dataType: "JSON",
success: function (data) {
alert("success");
},
error: function (data) {
alert("error");
}
});
What I need to do to achieve my goal..Your opinion will save my days...
I found my answer Session management in web api.
Please, read this Web Api Session storage before.
To retreive data from session use javascript sessionStorage (instead ajax).
I have been working with ajax and there has been no problems below is how my ajax post code look like:
$.ajax({
type: "POST",
url: '<%=ResolveUrl("TodoService.asmx/CreateNewToDo")%>',
data: jsonData,
contentType: "application/json; charset=utf-8",
datatype: "json",
success: function () {
//if (msg.d) {
$('#ContentPlaceHolder1_useridHiddenField').val("");
$('#ContentPlaceHolder1_titleTextBox').val("");
$('#ContentPlaceHolder1_destTextBox').val("");
$('#ContentPlaceHolder1_duedateTextBox').val("");
alert('Your todo has been saved');
// }
},
error: function (msg) {
alert('There was an error processing your request');
}
});
However, the problem came up when I try to get the url to a webservice that is located in a class library within the same solution.
This ASP.Net
says If you want to put the webservice in the classlibrary, you could try placing the Webservice.asmx.cs file in the class library and place the Webservice.asmx file in the web application project, and then using jquery to consume it in the .aspx page
If it's a different application than yours that's considered an XSS (Cross-site scripting) and it is not allowed.
You could however wrap the call to the external service in your own application (let's say in a REST service) and just call your service from jquery
The webservice code is simple:
[WebMethod]
[ScriptMethod(ResponseFormat = ResponseFormat.Json)]
public void receiveOrder(string json) {
Context.Response.Write("ok");
}
And the jquery calling the webservice is as follows:
$.ajax({
type: "POST",
contentType: "application/json; charset=utf-8",
url: 'http://localhost:50730/GingerWeb.asmx/receiveOrder',
data: 'test', //JSON.stringify(webOrder),
dataType: "text",
success: function(data){
if(data === "ok")
orderPlaced();
}
});
And yet the chrome console reads in provocative red:
500 (Internal Server Error)
The problem is that ASMX web-service need to find all input parameters in the request. If at least one input parameter will be not found in the request to the server the web service failed with the status code 500 (Internal Server Error).
The reason is that you send the data in the wrong way. The name of the input parameter of the web method is json (see void receiveOrder(string json)). So the data option of the $.ajax should be in the form
data: JSON.stringify({json: webOrder})
if you use type: "POST" instead of data: JSON.stringify(webOrder) which you tried before. In the case in the body of the POST request will be json=theVlue instead of just theValue.
If you would use type: "GET" the format of data parameter should be changed to
data: {json: JSON.stringify(webOrder)}
The value of the dataType should be 'json'. After the changes the $.ajax should work.
Moreover I would recommend you to use relative paths in the url option. I mean to use '/GingerWeb.asmx/receiveOrder' instead of 'http://localhost:50730/GingerWeb.asmx/receiveOrder'. It will save you from same origin policy errors.
Hello Oleg: Your explanation is simple and to the point. I had a similar problem which your explanation solved. I am providing code snippet to help 'searchers' understand what I was facing and how the above helped solve. In short I am issuing a simple jquery (.ajax) from a aspx page. I have created a webservice that gets some data from backend (cache/db) and return's the same in json format.
JS CODE:
var parameters = "{'pageName':'" + sPage + "'}"
var request = $.ajax({
type: "POST",
url: "/NotificationWebService.asmx/GetNotification",
data: parameters,
contentType: "application/json; charset=utf-8",
dataType: "json"
});
ASP.NET Code Behind for Web Service
[WebMethod]
[ScriptMethod(ResponseFormat = ResponseFormat.Json)]
public string GetNotification(string pageName)
{
JavaScriptSerializer js = new JavaScriptSerializer();
Notification ns = NotificationCache.GetActiveNotificationForPage(pageName);
if (ns != null)
{
NotificationJSData nJSData = new NotificationJSData();
nJSData.Code = ns.Code;
nJSData.displayFreq = (short)ns.DisplayFreq;
nJSData.expiryDate = ns.ToDateStr;
return js.Serialize(nJSData);
}
return null;
}
It is ABSOLUTELY necessary to ensure that you match 'pageName' variable name specified in web service code with what is sent in your data parameter of the ajax request. I had them different and changed it to be the same, after spending hours, I finally found the right solution, thanks to this post. Also, in my case I am only passing a single "name:value" pair so I didn't even have to use some json De-serialization function to get the value, pageName above gives me only the value.
A situation I ran across this week: we have a jQuery Ajax call that goes back to the server to get data
$.ajax(
{
type: "POST",
contentType: "application/json; charset=utf-8",
url: fullMethodPath,
data: data,
dataType: "json",
success: function(response) {
successCallback(response);
},
error: errorCallback,
complete: completeCallback
});
fullMethodPath is a link to a static method on a page (let's say /MyPage.aspx/MyMethod).
public partial class MyPage : Page
{
// snip
[WebMethod]
public static AjaxData MyMethod(string param1, int param2)
{
// return some data here
}
}
This works, no problem.
A colleague had attempted to replace this call with one where type was "GET". It broke, I had to fix it. Eventually, I went back to POST because we needed the fix quick, but it has been bugging me because semantically a GET is more "correct" in this case.
As I understand it, jQuery translates an object in data to a Query String: /MyPage.aspx/MyMethod?param1=value1¶m2=value2 but all I could get back was the content of the page MyPage.aspx.
Is that just a "feature" of Page methods, or is there a way of making a GET request work?
For security reasons, ASP.Net AJAX page methods only support POST requests.
It is true that ASP.NET AJAX page methods only support POST requests for security reasons but you can override this behavior by decorating your WebMethod with this these both attribute:
[WebMethod]
[ScriptMethod(UseHttpGet = true)]
I felt that the accepted answer was incomplete without pointing out a work around.
I have the following JQuery code that worked perfect in C#/Asp.net 2.0 to call a page method in the default.aspx page. Now I am trying to call a shared page method in VB.Net and the page method is not firing, I believe because of security or it is not finding it.
The page that this shared vb method is in doesn't allow anonymous access, so I was thinking that is the problem or it is a path problem to finding the method. I am just guessing here. In my C# test app the static webmethod was in the default.aspx page with no security. Thanks for any advice or help!
$.ajax({
type: "POST",
url: "Orders.aspx/GetMailPieceGroupsByAdFundTypeId",
data: myDataToSend,
contentType: "application/json; charset=utf-8",
dataType: "json",
//error: function(XMLHttpRequest, textStatus, errorThrown) {alert(errorThrown); this;},
success: function(data, textStatus){alert(success);mailPieceGroups = eval('(' + data + ')'); startSlideShow(mailPieceGroups); }
});
My issue was the path provided was not correct which caused the .ajax call not to be able to locate the method to call it.
This is correct for my scenario:
url: "../Orders.aspx/GetMailPieceGroupsByAdFundTypeId",