I created an ASMX file with a code behind file. It's working fine, but it is outputting XML.
However, I need it to output JSON. The ResponseFormat configuration doesn't seem to work. My code-behind is:
[System.Web.Script.Services.ScriptService]
public class _default : System.Web.Services.WebService {
[WebMethod]
[ScriptMethod(UseHttpGet = true,ResponseFormat = ResponseFormat.Json)]
public string[] UserDetails()
{
return new string[] { "abc", "def" };
}
}
Are you calling the web service from client script or on the server side?
You may find sending a content type header to the server will help, e.g.
'application/json; charset=utf-8'
On the client side, I use prototype client side library and there is a contentType parameter when making an Ajax call where you can specify this. I think jQuery has a getJSON method.
A quick gotcha that I learned the hard way (basically spending 4 hours on Google), you can use PageMethods in your ASPX file to return JSON (with the [ScriptMethod()] marker) for a static method, however if you decide to move your static methods to an asmx file, it cannot be a static method.
Also, you need to tell the web service Content-Type: application/json in order to get JSON back from the call (I'm using jQuery and the 3 Mistakes To Avoid When Using jQuery article was very enlightening - its from the same website mentioned in another answer here).
To receive a pure JSON string, without it being wrapped into an XML, you have to write the JSON string directly to the HttpResponse and change the WebMethod return type to void.
[System.Web.Script.Services.ScriptService]
public class WebServiceClass : System.Web.Services.WebService {
[WebMethod]
public void WebMethodName()
{
HttpContext.Current.Response.Write("{property: value}");
}
}
A quick gotcha that I learned the hard way (basically spending 4 hours on Google), you can use PageMethods in your ASPX file to return JSON (with the [ScriptMethod()] marker) for a static method, however if you decide to move your static methods to an asmx file, it cannot be a static method.
Also, you need to tell the web service Content-Type: application/json in order to get JSON back from the call (I'm using jQuery and the 3 Mistakes To Avoid When Using jQuery article was very enlightening - its from the same website mentioned in another answer here).
Alternative: Use a generic HTTP handler (.ashx) and use your favorite json library to manually serialize and deserialize your JSON.
I've found that complete control over the handling of a request and generating a response beats anything else .NET offers for simple, RESTful web services.
To receive a pure JSON string, without it being wrapped into an XML, you have to write the JSON string directly to the HttpResponse and change the WebMethod return type to void.
[System.Web.Script.Services.ScriptService]
public class WebServiceClass : System.Web.Services.WebService {
[WebMethod]
public void WebMethodName()
{
HttpContext.Current.Response.Write("{property: value}");
}
}
This is probably old news by now, but the magic seems to be:
With those pieces in place, a GET request is successful.
For a HTTP POST
and on the client side (assuming your webmethod is called MethodName, and it takes a single parameter called searchString):
$.ajax({
url: "MyWebService.asmx/MethodName",
type: "POST",
contentType: "application/json",
data: JSON.stringify({ searchString: q }),
success: function (response) {
},
error: function (jqXHR, textStatus, errorThrown) {
alert(textStatus + ": " + jqXHR.responseText);
}
});
Are you calling the web service from client script or on the server side?
You may find sending a content type header to the server will help, e.g.
'application/json; charset=utf-8'
On the client side, I use prototype client side library and there is a contentType parameter when making an Ajax call where you can specify this. I think jQuery has a getJSON method.
Alternative: Use a generic HTTP handler (.ashx) and use your favorite json library to manually serialize and deserialize your JSON.
I've found that complete control over the handling of a request and generating a response beats anything else .NET offers for simple, RESTful web services.
Are you calling the web service from client script or on the server side?
You may find sending a content type header to the server will help, e.g.
'application/json; charset=utf-8'
On the client side, I use prototype client side library and there is a contentType parameter when making an Ajax call where you can specify this. I think jQuery has a getJSON method.
Are you calling the web service from client script or on the server side?
You may find sending a content type header to the server will help, e.g.
'application/json; charset=utf-8'
On the client side, I use prototype client side library and there is a contentType parameter when making an Ajax call where you can specify this. I think jQuery has a getJSON method.
This is probably old news by now, but the magic seems to be:
With those pieces in place, a GET request is successful.
For a HTTP POST
and on the client side (assuming your webmethod is called MethodName, and it takes a single parameter called searchString):
$.ajax({
url: "MyWebService.asmx/MethodName",
type: "POST",
contentType: "application/json",
data: JSON.stringify({ searchString: q }),
success: function (response) {
},
error: function (jqXHR, textStatus, errorThrown) {
alert(textStatus + ": " + jqXHR.responseText);
}
});
A quick gotcha that I learned the hard way (basically spending 4 hours on Google), you can use PageMethods in your ASPX file to return JSON (with the [ScriptMethod()] marker) for a static method, however if you decide to move your static methods to an asmx file, it cannot be a static method.
Also, you need to tell the web service Content-Type: application/json in order to get JSON back from the call (I'm using jQuery and the 3 Mistakes To Avoid When Using jQuery article was very enlightening - its from the same website mentioned in another answer here).
Source: Stackoverflow.com