c# - Jquery ajax 响应返回 null

Question

我想从 Web 服务方法检索数据，但它返回 null。

我使用返回字符串的方法(Web 服务中的 GetTEST())进行测试，效果良好。

当我使用 WCFTestClient.exe 进行测试时，Statistic_1 方法运行良好，但使用 JQuery 时它返回 null。

这是 JavaScript 代码:

function getStatistic1() {

var response;
var allstat1 = [];

$.ajax({
    type: 'GET',
    url: 'http://localhost:52768/Service1/Statistic_1',
    contentType: 'application/json; charset=utf-8',
    dataType: 'json',
    success: function (msg) {
        response = msg.Items;
        console.log(msg);

        for (var i = 0; i < response.length; i++) {
            allstat1[i] = [response[i].Geografisch_zone];
        }
        fillDataTable(allstat1);
    },
    error: function (e) {
        alert("error loading statistic 1");
    }
});
}

这是我的 IService1.cs

[DataContractFormatAttribute]
[ServiceContract(Namespace ="WSSage100")]
public interface IService1
{

    [OperationContract]
    [WebInvoke(Method = "GET",ResponseFormat = WebMessageFormat.Json)]
    string GetTEST();

    [OperationContract]
    [WebInvoke(Method = "GET", ResponseFormat = WebMessageFormat.Json)]
    ResponseStatistic_1 Statistic_1();
}

这是Service1.svc

[AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Allowed)]
public class Service1 : IService1
{

    public string GetTEST()
    {
        return "OKKKKKKKK";
    }

    public ResponseStatistic_1 Statistic_1()
    {...}
}

这里是“console.log(msg)”显示:Object {ErrorMessage:“对象引用未设置到对象的实例。”, ErrorOccured: true, Items: null, NbRecord: 0}

ResponseSatistic_1 类:

public class ResponseStatistic_1 : IBaseClientEntity
{
    public ResponseStatistic_1()
    {

    }

    public ResponseStatistic_1(Statistic_1 [] items) : this()
    {
        this.Items = items;
    }

    #region Properties
    public Statistic_1[] Items
    {
        get;
        set;
    }
}

和 Statistic_1 类:

public class Statistic_1
{
    private string _geografisch_zone;
    private decimal[] _sum; 
    private int _yearStart;
    private int _yearEnd;

    ...
}

Answer 1

您正在返回字符串“OKKKKKK”，但您在$.ajax函数中将数据类型设置为JSON，因此您必须取消设置数据类型或返回类似“{响应:'OKKKK'}”。