Web 服务不返回序列化列表

Question

我为学习目的创建了一个简单的 Web 服务，它只实现了两种方法，一种是将对象添加到列表中，另一种是 return 列表。问题是该服务没有对象的序列化列表。 return 值是一个空数组。我在同一个解决方案中创建了一个简单的控制台应用程序，并使用 VS 2013 中的内置向导添加了一个服务引用。这些是生成的文件：http://i.imgur.com/ql0QUZN.png 这三个 .xsd 文件很奇怪，为什么不只有一个？

解决方案本身设置为多个启动项目（服务和客户端应用程序），"Start without debugging" 模式 - 如果这很重要。

WCF 测试客户端输出如下：

新学生电话 - http://i.imgur.com/Q41lq4L.png

StudentList 调用 - http://i.imgur.com/ULQULdW.png

如果需要，我会提供更多信息，在此先感谢您。

网络服务代码：

IService.cs

namespace CollegeService
{
    [ServiceContract]
    public interface IService
    {
        [OperationContract]
        List<Student> StudentList();

        [OperationContract]
        void NewStudent(Student s);
    }

    [DataContract]
    public class Student
    {
        private string _OIB; // unique identifier
        private string _name;
        private string _schoolYear;

        [DataMember]
        public string OIB
        {
            get { return _OIB; }
            set { _OIB = value; }
        }

        [DataMember]
        public string Name
        {
            get { return _name; }
            set { _name = value; }
        }

        [DataMember]
        public string SchoolYear
        {
            get { return _schoolYear; }
            set { _schoolYear = value; }
        }
    }
}

Service.svc

<%@ ServiceHost Language="C#" Debug="true" Service="CollegeService.Service" CodeBehind="Service.svc.cs" %>

Service.svc.cs

namespace CollegeService
{
    public class Service : IService
    {
        private List<Student> _students;

        public Service()
        {
            this._students = new List<Student>();
        }

        public void NewStudent(Student s)
        {
            this._students.Add(s);
        }

        public List<Student> StudentList()
        {
            return this._students;
        }
    }
}

客户代码：

Reference.cs

//------------------------------------------------------------------------------
// <auto-generated>
//     This code was generated by a tool.
//     Runtime Version:4.0.30319.34209
//
//     Changes to this file may cause incorrect behavior and will be lost if
//     the code is regenerated.
// </auto-generated>
//------------------------------------------------------------------------------

namespace CollegeServiceClient.Service {
    using System.Runtime.Serialization;
    using System;


    [System.Diagnostics.DebuggerStepThroughAttribute()]
    [System.CodeDom.Compiler.GeneratedCodeAttribute("System.Runtime.Serialization", "4.0.0.0")]
    [System.Runtime.Serialization.DataContractAttribute(Name="Student", Namespace="http://schemas.datacontract.org/2004/07/CollegeService")]
    [System.SerializableAttribute()]
    public partial class Student : object, System.Runtime.Serialization.IExtensibleDataObject, System.ComponentModel.INotifyPropertyChanged {

        [System.NonSerializedAttribute()]
        private System.Runtime.Serialization.ExtensionDataObject extensionDataField;

        [System.Runtime.Serialization.OptionalFieldAttribute()]
        private string NameField;

        [System.Runtime.Serialization.OptionalFieldAttribute()]
        private string OIBField;

        [System.Runtime.Serialization.OptionalFieldAttribute()]
        private string SchoolYearField;

        [global::System.ComponentModel.BrowsableAttribute(false)]
        public System.Runtime.Serialization.ExtensionDataObject ExtensionData {
            get {
                return this.extensionDataField;
            }
            set {
                this.extensionDataField = value;
            }
        }

        [System.Runtime.Serialization.DataMemberAttribute()]
        public string Name {
            get {
                return this.NameField;
            }
            set {
                if ((object.ReferenceEquals(this.NameField, value) != true)) {
                    this.NameField = value;
                    this.RaisePropertyChanged("Name");
                }
            }
        }

        [System.Runtime.Serialization.DataMemberAttribute()]
        public string OIB {
            get {
                return this.OIBField;
            }
            set {
                if ((object.ReferenceEquals(this.OIBField, value) != true)) {
                    this.OIBField = value;
                    this.RaisePropertyChanged("OIB");
                }
            }
        }

        [System.Runtime.Serialization.DataMemberAttribute()]
        public string SchoolYear {
            get {
                return this.SchoolYearField;
            }
            set {
                if ((object.ReferenceEquals(this.SchoolYearField, value) != true)) {
                    this.SchoolYearField = value;
                    this.RaisePropertyChanged("SchoolYear");
                }
            }
        }

        public event System.ComponentModel.PropertyChangedEventHandler PropertyChanged;

        protected void RaisePropertyChanged(string propertyName) {
            System.ComponentModel.PropertyChangedEventHandler propertyChanged = this.PropertyChanged;
            if ((propertyChanged != null)) {
                propertyChanged(this, new System.ComponentModel.PropertyChangedEventArgs(propertyName));
            }
        }
    }

    [System.CodeDom.Compiler.GeneratedCodeAttribute("System.ServiceModel", "4.0.0.0")]
    [System.ServiceModel.ServiceContractAttribute(ConfigurationName="Service.IService")]
    public interface IService {

        [System.ServiceModel.OperationContractAttribute(Action="http://tempuri.org/IService/StudentList", ReplyAction="http://tempuri.org/IService/StudentListResponse")]
        CollegeServiceClient.Service.Student[] StudentList();

        [System.ServiceModel.OperationContractAttribute(Action="http://tempuri.org/IService/StudentList", ReplyAction="http://tempuri.org/IService/StudentListResponse")]
        System.Threading.Tasks.Task<CollegeServiceClient.Service.Student[]> StudentListAsync();

        [System.ServiceModel.OperationContractAttribute(Action="http://tempuri.org/IService/NewStudent", ReplyAction="http://tempuri.org/IService/NewStudentResponse")]
        void NewStudent(CollegeServiceClient.Service.Student s);

        [System.ServiceModel.OperationContractAttribute(Action="http://tempuri.org/IService/NewStudent", ReplyAction="http://tempuri.org/IService/NewStudentResponse")]
        System.Threading.Tasks.Task NewStudentAsync(CollegeServiceClient.Service.Student s);
    }

    [System.CodeDom.Compiler.GeneratedCodeAttribute("System.ServiceModel", "4.0.0.0")]
    public interface IServiceChannel : CollegeServiceClient.Service.IService, System.ServiceModel.IClientChannel {
    }

    [System.Diagnostics.DebuggerStepThroughAttribute()]
    [System.CodeDom.Compiler.GeneratedCodeAttribute("System.ServiceModel", "4.0.0.0")]
    public partial class ServiceClient : System.ServiceModel.ClientBase<CollegeServiceClient.Service.IService>, CollegeServiceClient.Service.IService {

        public ServiceClient() {
        }

        public ServiceClient(string endpointConfigurationName) : 
                base(endpointConfigurationName) {
        }

        public ServiceClient(string endpointConfigurationName, string remoteAddress) : 
                base(endpointConfigurationName, remoteAddress) {
        }

        public ServiceClient(string endpointConfigurationName, System.ServiceModel.EndpointAddress remoteAddress) : 
                base(endpointConfigurationName, remoteAddress) {
        }

        public ServiceClient(System.ServiceModel.Channels.Binding binding, System.ServiceModel.EndpointAddress remoteAddress) : 
                base(binding, remoteAddress) {
        }

        public CollegeServiceClient.Service.Student[] StudentList() {
            return base.Channel.StudentList();
        }

        public System.Threading.Tasks.Task<CollegeServiceClient.Service.Student[]> StudentListAsync() {
            return base.Channel.StudentListAsync();
        }

        public void NewStudent(CollegeServiceClient.Service.Student s) {
            base.Channel.NewStudent(s);
        }

        public System.Threading.Tasks.Task NewStudentAsync(CollegeServiceClient.Service.Student s) {
            return base.Channel.NewStudentAsync(s);
        }
    }
}

Program.cs（入口点）

namespace CollegeServiceClient
{
    public class Program
    {
        static void Main(string[] args)
        {
            ServiceClient client = new ServiceClient();
            try
            {
                client.Open();
                client.NewStudent
                    (new Student
                        {
                            OIB = "1234",
                            Name = "John Doe",
                            SchoolYear = "4"
                        }
                    );
                Student[] students = client.StudentList();
                foreach (Student s in students)
                {
                    Console.WriteLine("Student OIB: {0} Name: {1} School year: {2}", s.OIB, s.Name, s.SchoolYear);
                }
            }
            catch (Exception e)
            {
                Console.WriteLine(e.Message);
            }
            finally
            {
                client.Close();
            }
        }
    }
}

Answer 1

原来问题和解释的一样here。在你的例子中，new Service class 实例被实例化 per call，因此，你的列表是总是被重置。

要解决这个问题，只需将 [ServiceBehavior(InstanceContextMode = InstanceContextMode.Single, ConcurrencyMode = ConcurrencyMode.Single)] 属性添加到您的 Service class。这应确保使用相同的 class 实例来处理您的呼叫。

我的代码是这样的：

namespace CollegeService
{
    // NOTE: You can use the "Rename" command on the "Refactor" menu to change the interface name "IService1" in both code and config file together.
    [ServiceContract]
    public interface IService
    {
        [OperationContract]
        List<Student> StudentList();

        [OperationContract]
        void NewStudent(Student s);
    }

    // Use a data contract as illustrated in the sample below to add composite types to service operations.
    // You can add XSD files into the project. After building the project, you can directly use the data types defined there, with the namespace "CollegeService.ContractType".
    [DataContract]
    public class Student
    {

        [DataMember]
        public string OIB
        {
            get;
            set;
        }

        [DataMember]
        public string Name
        {
            get;
            set;
        }

        [DataMember]
        public string SchoolYear
        {
            get;
            set;
        }
    }
}

namespace CollegeService
{
    // NOTE: You can use the "Rename" command on the "Refactor" menu to change the class name "Service1" in both code and config file together.
    [ServiceBehavior(InstanceContextMode = InstanceContextMode.Single, ConcurrencyMode = ConcurrencyMode.Single)]
    public class Service : IService
    {
        private List<Student> _students;

        public Service()
        {
            this._students = new List<Student>();
        }

        public void NewStudent(Student s)
        {
            this._students.Add(s);
        }

        public List<Student> StudentList()
        {
            return this._students;
        }
    }
}

Web 服务不返回序列化列表

web service not returning a serialized list

.net

c#

wcf

web-services