Question

System.InvalidOperationException: There was an error generating the XML document. ---> System.InvalidOperationException: A circular reference was detected while serializing an object of type projectnetwork.Models.Branch.
   at System.Xml.Serialization.XmlSerializationWriter.WriteStartElement(String name, String ns, Object o, Boolean writePrefixed, XmlSerializerNamespaces xmlns)
   at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationWriter1.Write7_Branch(String n, String ns, Branch o, Boolean isNullable, Boolean needType)
   at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationWriter1.Write6_Company(String n, String ns, Company o, Boolean isNullable, Boolean needType)
   at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationWriter1.Write7_Branch(String n, String ns, Branch o, Boolean isNullable, Boolean needType)
   at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationWriter1.Write8_Branch(Object o)
   at System.Xml.Serialization.XmlSerializer.Serialize(XmlWriter xmlWriter, Object o, XmlSerializerNamespaces namespaces, String encodingStyle, String id)
   --- End of inner exception stack trace ---
   at System.Xml.Serialization.XmlSerializer.Serialize(XmlWriter xmlWriter, Object o, XmlSerializerNamespaces namespaces, String encodingStyle, String id)
   at System.Xml.Serialization.XmlSerializer.Serialize(TextWriter textWriter, Object o, XmlSerializerNamespaces namespaces)
   at System.Web.Services.Protocols.XmlReturnWriter.Write(HttpResponse response, Stream outputStream, Object returnValue)
   at System.Web.Services.Protocols.WebServiceHandler.WriteReturns(Object[] returnValues)
   at System.Web.Services.Protocols.WebServiceHandler.Invoke()

几个小时前，到目前为止我无法解决这个问题و我真的很累，而且在我变得疯狂之前的最后一次机会:)我能找到解决这个问题的人吗？我要做的是返回类型为branch的对象，即子公司包含其父公司的对象，即公司。

分类

public partial class Branch
{
    public Branch()
    {
        this.Customers = new List<Customer>();
    }

        public int BranchID { get; set; }
        public int CompanyID { get; set; }
        public string BranchName { get; set; }
        public string BranchShortName { get; set; }
        public string BranchAddress { get; set; }
        public string BranchPhone { get; set; }
        public string BranchEmail { get; set; }
        public string BranchFax { get; set; }
        public Nullable<float> BranchLimit { get; set; }
        public bool RecordState { get; set; }
        public virtual Company Company { get; set; }        
    }

公司类

public partial class Company
{
    public Company()
    {
        this.Branches = new List<Branch>();
    }

    public int CompanyID { get; set; }
    public string CompanyName { get; set; }
    public string CompanyShortName { get; set; }
    public string CompanyAddress { get; set; }
    public string CompanyPhone { get; set; }
    public string CompanyEmail { get; set; }
    public string CompanyFax { get; set; }
    public bool RecordState { get; set; }
    public virtual List<Branch> Branches { get; set; }
}

NewDBContext类

using System.Data.Entity;
using System.Data.Entity.Infrastructure;
using projectnetwork.Models.Mapping;

namespace projectnetwork.Models
{
public partial class NewDBContext : DbContext
{
    static NewDBContext()
    {
        Database.SetInitializer<NewDBContext>(null);
    }

    public NewDBContext()
        : base("Name=NewDBContext")
    {
        this.Configuration.LazyLoadingEnabled   = false;
        this.Configuration.ProxyCreationEnabled = false;
    }

    public DbSet<Branch> Branches { get; set; }
    public DbSet<Company> Companies { get; set; }

    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        modelBuilder.Configurations.Add(new BranchMap());
        modelBuilder.Configurations.Add(new CompanyMap());          
    }
}
}

通话方法

    [WebMethod]
    public Branch getAllCustomers()
    {
        Branch  br = null;

        using (var db = new NewDBContext())
        {
            br = db.Branches
                .Where(d => d.CompanyID == 1)
                .Include(c => c.Company)
                .FirstOrDefault<Branch>();                  


            return br;

        }

抱歉我的英文不好

Answer 1

如果您使用的是Newtonsoft.Json，可以尝试在类上添加JsonIgnore属性以停止呈现

public partial class Company
{
    public Company()
    {
        this.Branches = new List<Branch>();
    }

    ....

    [JsonIgnore]
    public virtual List<Branch> Branches { get; set; }

}

Answer 2

您似乎需要将DataContract属性的IsReference属性设置为true。一些额外的细节是here。

[DataContract(IsReference = true)]

System.InvalidOperationException：检测到循环引用

2 个答案: