Question

我正在迈出第一步，这需要对我的应用程序进行内部处理，并将其全部重新设计为3层和面向对象。嗟。我有一个提交对象，它应该包含一个客户对象（以及一个代理和覆盖对象）;我想在每个包含的对象的字段中存储来自db的一些datareader结果，但是当我尝试使用新的提交对象调用Customer对象时，我什么也得不到。 VS无法识别Submission包含Customer对象。我显然错过了一些关键点，所以考虑到这一点，想法？代码如下。

//This is the Submission class here
public class Submission 
{
    public int SubmissionId {get;set;}
    public int Status { get; set; }
    public string StatusComment { get; set; }


    public class Customer
    {
        //public Customer() { }
        public int CustId { get; set; }
        public string CustName { get; set; }
        public string CustAddress { get; set; }
        public string CustState { get; set; }
        public string CustCity { get; set; }
        public int CustZip { get; set; }
        public int SicNaic { get; set; }

    }

    public object Customer();
}


//These lines throw an error:

无法通过表达式引用类型。 VS无法识别TempSubmission.Customer提交的Customer对象。

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Data;
using System.Data.SqlClient;


/// This query should selects the relevant data for a gridview on the presentation layer and stores in a list. 
/// Don't quite know how to bind it to the gridview yet, but that's a different question. 

public class SubmissionDatabaseService
{
    public List<Submission> GetAllSubmissions()
    {
        string Searchstring = "SELECT Submission.SubmissionId, Customer.CustName, Customer.CustCity, Customer.CustState, Broker.BroName, Broker.BroState, Broker.EntityType, Submission.Coverage, Status.Status FROM Submission INNER JOIN Broker ON Broker.BroId = Submission.BroId INNER JOIN Customer ON Customer.CustId = Submission.CustId INNER JOIN Status ON Status.StatusId = Submission.StatusId";
        string connectionString = System.Configuration.ConfigurationManager.ConnectionStrings["MyConnectionString"].ConnectionString;        
        SqlConnection conn = new SqlConnection(connectionString);

        SqlDataReader dr = null;

        try
        {
            conn.Open();

            SqlCommand Searchcmd = new SqlCommand(Searchstring, conn);

            dr = Searchcmd.ExecuteReader();
            List <Submission> lstSubmission;
            Submission tempSubmission;
            while (dr.Read())
            {
                tempSubmission = new Submission();
                tempSubmission.SubmissionId = dr.GetInt32(0);
                tempSubmission.Customer.CustName = dr.GetString(1);
                tempSubmission.Customer.CustCity = dr.GetString(2);
                tempSubmission.Customer.CustState = dr.GetString(3);
                tempSubmission.Broker.BroName = dr.GetString(4);
                tempSubmission.Broker.BroState = dr.GetString(5);
                tempSubmission.Broker.EntityType = dr.GetString(6);
                tempSubmission.SubmissionCoverage.Coverage = dr.GetInt32(7);
                tempSubmission.Status = dr.GetInt32(8);

                //Add rest of the fields
                lstSubmission.Add(tempSubmission);
            }
        }

        return lstSubmission;
    }
}

Answer 1

噢..从哪里开始？将Customer类放在自己的文件Customer.cs中，将Submission类放在自己的文件Submission.cs

中

然后你可以这样做一个简单的提交类：

public class Submission 
{
        // consider implementing the below as properties to more finely control access
        public int SubmissionId;
        public int Status;
        public string StatusComment;
        public Customer SubmissionCustomer; // <-- this is null until you set it to a Customer object, either in the constructor or externally.

        public Submission() {
          // constructor
        }

}

然后阅读属性和构造函数，并按照您认为合适的方式进行处理。参见：

http://msdn.microsoft.com/en-us/library/x9fsa0sw(v=vs.80).aspx

属性具有私有/公共模式。至于构造函数：

请参阅：

http://msdn.microsoft.com/en-us/library/ace5hbzh.aspx

每当您创建类的实例（对象）时，都会调用

构造函数。

Answer 2

我认为你想要的是Customer类在Submission类之外，并且Submission类包含Customer的实例。

public class Submission
{
    public Submission()
    {
        this.Customer = new Customer();
    }

    public int SubmissionId { get; set; }
    public int Status { get; set; }
    public string StatusComment { get; set; }
    public Customer Customer { get; set; }
}
public class Customer
{
    //public Customer() { }
    public int CustId { get; set; }
    public string CustName { get; set; }
    public string CustAddress { get; set; }
    public string CustState { get; set; }
    public string CustCity { get; set; }
    public int CustZip { get; set; }
    public int SicNaic { get; set; }
}

Answer 3

仅在Submission中定义Customer对象不会使Submission包含Customer实例。对于您想要做的事情，只需将Customer置于Submission之外，并在Submission内定义Customer属性。

Answer 4

您尝试通过Customer引用实际的tempSubmission类型。您必须改为引用Customer的实例，该实例将通过属性或类似内容公开。

Answer 5

问题是您的客户类型不是特定的，它被定义为对象而不是客户。

要实现您想要做的事情，您必须在Customer课程中添加一个新成员，在这种情况下为Submission类型的属性，您对public object Customer();所做的基本上是meams ，定义一个名为Customer的类型为对象的方法。

您要做的是定义一个名为Customer的属性，称为“任意”，例如RelatedCustomer

Public Customer RelatedCustomer{get;set;}

在另一个C＃中创建一个对象？

5 个答案: