I have a .NET 3.5 aspx place with a method marked with the [WebMethod] attribute. I'm calling this with jQuery, sending JSON in both directions. This all works great. My question is, what does [ScriptMethod] do when applied to an method? I've tried this and it seems to yield the same result. Are ScriptMethod and WebMethod identical and interchangeable, or does one provide functionality and/or overhead that the other doesn't? In general, I find myself confused with all of the options available for implementing web services and I'd like to know what the pros and cons are for each.
You use the ScriptMethod attribute in the following 2 scenarios.
You are using jquery or any other ajax request mechanism, but you want the request to be a GET not a POST.
You want to receive an XML formated response in javaScript.
If you don't have one of the above requirements; you just need a JSON response using a an ajax request then you can simply use the WebMethod.
There is still one more confusing element here, when do you use the ScriptService attribute? this is used if you are using the Microsoft Ajax Client script framework, this attributes tell the server to generate proxy objects on the client so that you can call functions just like a normal object. var MyRemoteObject = new RemoteObject(); MyRemoteObject.getMessage(....) and even when you use the ScriptService attribute you don't need to add the ScriptMethod attribute only in the above scenarios.
It was confusing to me at the begining because i thought that the ScriptService and the ScriptMethod attributes works together just like the WebService and WebMethod attributes.
The ScriptMethodAttribute attribute is optional. (However, methods that can be called from client script must have the System.Web.Services..::.WebMethodAttribute attribute applied.). If a method is not marked with ScriptMethodAttribute, the method will be called by using the HTTP POST command and the response will be serialized as JSON. You cannot override this setting from script.
from - http://msdn.microsoft.com/en-us/library/system.web.script.services.scriptmethodattribute.aspx
EDIT: WebMethod and ScriptMethod are not competing attributes. ScriptMethod could be an additional annotation, as the above para says.
Related
Here's my problem.
I'm using SOAP to retrieve information from a third-party web service.
Response time is too high, so I was planning on using JSON instead, at least in a couple of methods.
For this I'm using DataContractJsonSerializer, but I seem to be having some trouble.
For example, in SOAP there's a method called getAvailablePublic with returns an object of type getAvailablePublicResponse.
There's an equivalent for this method in JSON, which also returns a an object of type getAvailablePublicResponse.
In order to deserialize the information I needed to create a couple of data contracts, and here are my concerns:
Do I really need to create a DataContract? Why can't I use getAvailablePublicResponse object from asmx?
The problem is that if I create a DataContract, I need to use a different name other than getAvailablePublicResponse, as I would have two objects with the same name (the one created by me, and the one from SOAP), and this would require making several changes in my solution.
Hope this makes sense.
Thanks.
Can you post your client code that is making the call to the web service? I don't know what you are using now, but I'm a fan of RestSharp for making remote calls and serializing JSON to C# classes. Something like this:
RestClient client = new RestClient("http://some.domain.com/someservice?someparam=yes");
var results = client.Execute<MyGreatDTOClass>(new RestRequest(Method.GET));
Is there a way in ASP.net to fetch data from database using Jquery Ajax Method. I know that i can easily access the data by creating a webservice and get it from there using Ajax.
What I want to know is that how can I get the data from simple class methods which accesses the database rather than creating a webservice.
One way can be is to write a HTTPHandler and call that handler using Jquery to retrieve the data.
Check this out for a super-easy (lazy) way of doing a return straight from a public method defined in your aspx.cs file:
asp.net web forms json return result
Example shows putting [WebMethod] and [ScriptMethod(ResponseFormat = ResponseFormat.Json)] attributes on top of the method allows you to call directly from ajax client side request. Worth considering securing this method though to prevent calls from elsewhere!
I have an ASP.NET WebApi application that has some controller methods that expect certain strings to be passed in as method parameters (declared as part of the route template).
On all the methods, the strings passed in are base64-encoded -- which means each controller method must base64-decode them before doing anything with them. While I can obviously have each method do this easily enough, I was wondering if there was a way to perform the decoding before the string actually gets passed to the controller method. I presume this is something along the lines of an action filter or custom formatter, but I'm not familiar enough with asp.net web api to know where to start on that?
Summary:
I've got route templates like : {controller}/{encodedString}/whatever
where {encodedString} is always a base64-encoded string.
and controllers with methods like
GetWhatever(string encodedString)
{
Base64Decode(encodedString);
// do other stuff...
}
I would like to use some part of the asp.net webapi pipeline to decode {encodedString} before the controller method is actually called. What path should I start down in order to do this?
You can create a custom model binder and attach it to the parameters using the ModelBinderAttribute. In the model binder you then do the base64 decoding.
For a reference on parameter binding in Web API check:
How WebAPI does Parameter Binding
I need to get some Json to the client side from the server and it's somewhat troublesome as almost all tutorials assume an Ajax call to a separate action to get the Json.
This led me to think that there must be some reason why it is done this way. In Asp.Net MVC we can pass a Model along with the view to get the information but we can't seem to easily pass a Json object. Instead you are supposed to make a separate call to get this information.
What if the Json info is known when the page is generated, why not generate it at the same time?
I'm sorry if I wasn't clear enough. While it's nice to hear of ways to get Json to the client, the question is actually whether there is a specific reason the Ajax call method is much more popular, like security or anything like that.
Can you put something like this into your view? (rough pseudo code, assuming using a Razor view)
< script >
var myJSON = { Field: #model.Field, Field2: #model.Field2 };
< /script >
Because you do not need both at the same time... on the first call will be to get html (the view of the data - represented by a view model), and any ajax calls will be to get the possibly updated data (json serialized view model).
No reason why you can't. You could use the javacript serializer to create a JSON string that drop on the page. You could also create an action that return the json string that you called from a script tag.
What you want if you're using KnockOut, would be the Mapping plugin that turns an ordinary JS object, like that generated above, into an observable ready for KnockOut to use. See here from info. http://knockoutjs.com/documentation/plugins-mapping.html
You can use content-negotiation by setting accept header. This is considered a best practice (and according to some RESTful).
This needs to be supported and implemented at server as well. ASP NET MVC does not make it easy to support content-negotiation and you have to implement it yourself by if-else or using ActionFilter and implementing action selector.
All literature I see on creating custom handlers deals with associating an extension with a handler, e.g. if I wanted a handler for Ajax requests, I could implement the IHttpHandler interface in an AjaxHandler class.
Now, to have individual instances of AjaxHandlers, e.g. DocAjaxHander, PersonAjaxHandler etc. how would I derive the base AJAX handling of my AjaxHandler class without registering each individual *.ajax page?
It sounds like your assuming 1 HttpHandler = 1 Page or 1 Control, but as I understand, 1 HttpHandler can handle all pages of a certain file extension.
Your Question is not very clear, and your reponse to another answerer makes no sense...
"In fact, it seemed, to me, a lot like I was asking Http handlers, using a .ajax handler as an example."
But I shall assume you are thinking "DocAjaxHander" and "PersonAjaxHandler" should each be created for a "DocAjaxControl" and "PersonAjaxControl" respectively. I dont think that would be neccesary, 1 handler should be able to handle all your ajax requests if you choose to do it that way, but it doesn't feel like the most intuitive solution to me (using HttpHandlers), anyway, onto the details...
every IHttpHandler object needs to implement :
public void ProcessRequest(HttpContext context)
which allows :
context.Response.Write("Your JSON Response in here");
but at the level of 'ProcessRequest()', you have no access to the instance of the control which created the ajax call, or to the 'System.Web.UI.Page' object that holds the control, or anything.
context.Request
to the rescue! With the Request object above you can read QueryStrings, Sessions, an you can determine the path of the original HttpRequest (i.e. PersonAjaxObject may make an ajax call to 'myPersonobjPage.ajax' for its JSON data, but the '.ajax' extention lands the request at your custom http handler and it's ProcessRequest method.)
If I was you, and I was going to use an HttpHandler for my ajax calls, I'd use query string data to provide enough info for my handler to know 'what type of object am I responding too' as well as 'what data is that object requesting'.
Hope that helps.
You can automatically handle AJAX request in a number of ways. Here's how to do it with a web service:
http://www.asp.net/AJAX/Documentation/Live/Tutorials/ConsumingWebServicesWithAJAXTutorial.aspx
Well, one way to do it would be via query string params...