An attempt was made to call the method \u0027GetNextImage\u0027 using a GET request, which is not allowed

问题

I have a web method GetNextImage in my client script. In ASPX page I have the following code.

function slideshow() {
  $.ajax({
    type: "GET",
    contentType: "application/json; charset=utf-8",
    url: "/RollingScreen.aspx/sample",
    dataType: "json",
    data: "{}",
    success: function (data) {
      //this changes the image on the web page
      $('#imgSlideShow').attr("src","~/Images/1.png");

      //fires another sleep/image cycle
      setTimeout(slideshow(), 5000);
    },
    error: function (result) {
      alert(result.message);
    }
  });
}

$(document).ready(function () {
  //Kicks the slideshow
  slideshow();
});

I am getting the error as below.

{"Message":"An attempt was made to call the method \u0027GetNextImage\u0027 using a GET request, which is not allowed.","StackTrace":" at System.Web.Script.Services.RestHandler.GetRawParams(WebServiceMethodData methodData, HttpContext context)\r\n at System.Web.Script.Services.RestHandler.ExecuteWebServiceCall(HttpContext context, WebServiceMethodData methodData)","ExceptionType":"System.InvalidOperationException"}

Please can anyone help me. Thanks in advance.

回答1:

Add attribute to you WebMethod to indicate using of HTTP GET.

[WebMethod(EnableSession = true)]
[System.Web.Script.Services.ScriptMethod(UseHttpGet = true, ResponseFormat = System.Web.Script.Services.ResponseFormat.Json)]
public static string sample()
{
   //Your Code Which Gets Next Image 
}

You shouldn't use POST instead of GET.

"POST requests can't be bookmarked, send in an email or otherwise be reused. They screw up proper navigation using the browsers back/forward buttons. Only ever use them for sending data to the server in one unique operation and (usually) have the server answer with a redirect." - deceze (Is there anything not good using POST instead of GET?)

来源：https://stackoverflow.com/questions/13339929/an-attempt-was-made-to-call-the-method-u0027getnextimage-u0027-using-a-get-requ

标签

jquery