Ajax cross-origin access to webservice and ajax cross-origin webservice

Ajax cross-origin access to webservice and ajax cross-origin webservice

Front-end code

    $.ajax({            type: "POST",            url: "http://localhost:9767/WebService1.asmx/HelloWorld?jsoncallback=?",            data: "{}",            dataType: "jsonp",            success: function (data) {                                alert(data.result);            }        });

Webservice code

  public void HelloWorld()        {            string callbackMethodName = HttpContext.Current.Request.Params["jsoncallback"] ?? "";            HttpContext.Current.Response.Write(callbackMethodName + "({result:'Hello World'})");            HttpContext.Current.Response.End();                  }

This will get

 

 

However, if such code is used

If the url is not added? Jsoncallback =?

 

  $(function () {        $.ajax({            type: "POST",            url: "http://localhost:9767/WebService1.asmx/HelloWorld",            data: "{}",            dataType: "jsonp",            success: function (data) {                alert(data.result);            }        });

　　

  public string HelloWorld()        {            return "Hello World";        }

　　

Then, an xml (

<?xml version="1.0" encoding="utf-8"?><string xmlns="http://tempuri.org/">Hello World</string>

) And I will not go back to the callback function. I don't know much about webservice, and I have just been familiar with it. I would like to express my gratitude to you.