从 jQuery 调用 ASMX

我试图从 jQuery 调用 ASMX 方法，但没有成功。以下是我的代码，我不明白我缺少什么。

文件Something.js，

function setQuestion() {
    $.ajax({
        type: "POST",
        data: "{}",
        dataType: "json",
        url: "http: //localhost/BoATransformation/Survey.asmx/GetSurvey",
        contentType: "application/json; charset=utf-8",
        success: onSuccess
    });
}

function onSuccess(msg) {
    $("#questionCxt").append(msg);
}

文件SomethingElse.cs，

[WebService(Namespace = "http://tempuri.org/")]
[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
[System.Web.Script.Services.ScriptService]
public class Survey : System.Web.Services.WebService {

    public Survey () {
    }

    [WebMethod]
    [ScriptMethod(UseHttpGet = true)]
    public string GetSurvey() {
        return "Question: Who is Snoopy?";
    }
}

突出的一件事是你有UseHttpGet=true但在你的 jQuery 代码中你使用的是 POST。

这里还有一个我创建的调用 ASMX 页面的测试页面。

[WebMethod]
public Catalog[] GetCatalog()
{
    Catalog[] catalog = new Catalog[1];
    Catalog cat = new Catalog();
    cat.Author = "Jim";
    cat.BookName ="His Book";
    catalog.SetValue(cat, 0);
    return catalog;
}

<script type="text/javascript">
    $(document).ready(function() {
    $.ajax({
            type: "POST",
            url: "default.asmx/GetCatalog",
            cache: false,
            contentType: "application/json; charset=utf-8",
            data: "{}",
            dataType: "json",
            success: handleHtml,
            error: ajaxFailed
        });
    });

    function handleHtml(data, status) {
        for (var count in data.d) {
            alert(data.d[count].Author);
            alert(data.d[count].BookName);
        }
    }

    function ajaxFailed(xmlRequest) {
        alert(xmlRequest.status + ' \n\r ' + 
              xmlRequest.statusText + '\n\r' + 
              xmlRequest.responseText);
    }
</script>