我如何从ASMX Web服务返回用户定义的对象

    [WebMethod]
    public engineer getItem()
    {
        DataClasses1DataContext db = new DataClasses1DataContext();
        List<string> list = new List<string>();
        string tcNo="13609224456";
        var bilgiler = db.bilgilers.First(c => c.tc_kimlik_no ==tcNo);

        string adi = bilgiler.adi;
        string soyadi = bilgiler.soyadi;
        string universite = bilgiler.universite;
        engineer e = new engineer(tcNo, adi, soyadi, universite);

        return e;
    }

我有多个方法,并且可以无错误地运行Web服务,但是当我调用getItem()方法时,出现以下异常.我该如何解决该问题？

[InvalidOperationException: Parametresiz oluşturucusu olmadığından MUHENDIS.Service1.engineer seri hale getirilemez.]
   System.Xml.Serialization.TypeDesc.CheckSupported() +3938411
   System.Xml.Serialization.TypeScope.GetTypeDesc(Type type, MemberInfo source, Boolean directReference, Boolean throwOnError) +170
   System.Xml.Serialization.XmlReflectionImporter.ImportMemberMapping(XmlReflectionMember xmlReflectionMember, String ns, XmlReflectionMember[] xmlReflectionMembers, Boolean rpc, Boolean openModel, RecursionLimiter limiter) +65
   System.Xml.Serialization.XmlReflectionImporter.ImportMembersMapping(XmlReflectionMember[] xmlReflectionMembers, String ns, Boolean hasWrapperElement, Boolean rpc, Boolean openModel, RecursionLimiter limiter) +236

[InvalidOperationException: 'getItemResult' yansıtmada bir hata oluştu.]
   System.Xml.Serialization.XmlReflectionImporter.ImportMembersMapping(XmlReflectionMember[] xmlReflectionMembers, String ns, Boolean hasWrapperElement, Boolean rpc, Boolean openModel, RecursionLimiter limiter) +843
   System.Xml.Serialization.XmlReflectionImporter.ImportMembersMapping(String elementName, String ns, XmlReflectionMember[] members, Boolean hasWrapperElement, Boolean rpc, Boolean openModel, XmlMappingAccess access) +130
   System.Web.Services.Protocols.SoapReflector.ImportMembersMapping(XmlReflectionImporter xmlImporter, SoapReflectionImporter soapImporter, Boolean serviceDefaultIsEncoded, Boolean rpc, SoapBindingUse use, SoapParameterStyle paramStyle, String elementName, String elementNamespace, Boolean nsIsDefault, XmlReflectionMember[] members, Boolean validate, Boolean openModel, String key, Boolean writeAccess) +223
   System.Web.Services.Protocols.SoapReflector.ReflectMethod(LogicalMethodInfo methodInfo, Boolean client, XmlReflectionImporter xmlImporter, SoapReflectionImporter soapImporter, String defaultNs) +2989

编辑：Google将例外消息翻译为以下内容：

> MUHENDIS.Service1.engineer不能序列化无参数构造函数.
>’getItemResult’以反映发生的错误.

解决方法:

您需要确保工程师类标记为可序列化.

[Serializable]
public class engineer{ ....

标签：asmx,web-services,c,object
来源： https://codeday.me/bug/20191030/1970106.html