使用ajax（）和jsonp调用asp.net远程Web服务.asmx时出现意外令牌<

Question

I have a very basic - for testing - ASP.net Web service (2.0 and IIS 6.0) written in VB running on a remote server

WEB SERVICE

 <WebService(Namespace:="CMS_ChecklistSystemWebService")> _
 <WebServiceBinding(ConformsTo:=WsiProfiles.BasicProfile1_1)> _
 <Global.Microsoft.VisualBasic.CompilerServices.DesignerGenerated()> _
 <System.Web.Script.Services.ScriptService()> _
 Public Class CMS_ChecklistSystemWebService
    Inherits System.Web.Services.WebService
    <WebMethod()> _
    Public Function HelloWorld() As String
        Return "Hello World"
    End Function

CONFIG.

i had to add these following lines to my webservice config in order to be able to run the webservice in a Browser

<system.web>
    <webServices>
        <protocols>
            <add name="HttpGet"/>
            <add name="HttpPost"/>
        </protocols>
    </webServices>
</system.web>

**WEB SERVICE OUTCOME **

I was trying to call this web service from PHP page using AJAX JQUERY running XAMPP v3.1

JQUERY

  $.ajax({
        type: "GET",
        url: "http://192.168.25.11/link to web service",
            data: "",
            dataType: "jsonp",
            contentType: "application/jsonp; charset=utf-8",
            success: function(data) {
                console.log(data);
            }
        });

ERROR

Following is how my console looks like after calling the ajax() function

FYI if i click on the link in the second line it will link you to the webservice and run it as in the first image

NOTICE

if i use the same webservice from the same project - domain - i can easily do ajax() call and type='json' and it works perfectly with no errors

Question

• What i'm doing wrong ?
• Do i need to make the Webservice return a JSON object instead of XML if yes then how

Answer 1

I think the problem is, you are specifying content type as json in ajax call. But, your web service is returning xml.

So, either you can specify content type as xml in ajax call and process the xml (I am not sure whether it is possible or not), or you can configure web service to return json.

Refer this SO question ( How to return JSON from a 2.0 asmx web service ) to configure web service to return json.

Answer 2

Rumit has, I think, only given part of the answer here. You certainly need to set your web service to return JSON instead of XML.

However, you've stated that you're setting dataType: "jsonp" This requires that you return your JSON inside a method call with the name of the method being the value of the callback key in your second image above.

for example, it would look something* like this :

jQuery1910366312976758182({data: "Hello World"})

*not exactly, but step through and you'll get the idea...