Question

Web服务以业务逻辑Graph.AddressList导入数据和存储。如果找到匹配项，请添加到keepList。问题是数据完全相同，但没有添加到保留列表中。例如，如果没有写出数据库中的每一列以匹配xmlRecord中的每一列，则填充数据库中的记录中的ENTITYKEY但不在Xml中。有办法解决这个问题吗？

// Fetch List Of Addresses
List<Address> updateAddressList = DbContext.GraphAddressList.Where<Address>(p => p.PersonnelNo == action.PersonnelNo).ToList<Address>();

////IF ADDRESS EXISTS IN THE DB, BUT NOT IN THE XML FILE, REMOVE FROM DB
List<Address> keepList = new List<Address>();
foreach (Address recordInDB in updateAddressList)
{
    foreach (Address_0006 recordInXML in Graph.AddressList)
    {
        if (recordInDB == recordInXML)
        {                                                        
            keepList.Add(recordInDB);
        }
    }
}

List<Address> removeList = updateAddressList.Except(keepList).ToList();
foreach (Address record in removeList)
{                                           
    DbContext.AddressList.DeleteObject(record);
}

感谢您的回复，所以我需要创建一个类

 public override bool Equals(object obj)
{
    var item = obj as RecommendationDTO;

    if (item == null)
    {
        return false;
    }

    return this.RecommendationId.Equals(item.RecommendationId);
}

public override int GetHashCode()
{
    return this.RecommendationId.GetHashCode();
}

Answer 1

recordInDB和recordInXML是自定义对象，要检查它们是否相等，您必须：

为他们覆盖Equals和GetHashCode：Correct way to override Equals() and GetHashCode()
实施IEqualityComparer：How to use the IEqualityComparer
让其中一个类实现IEquatable<T>，其中T是另一个类的类型

这样做的对象将通过他们拥有的属性进行比较。目前（x == y）检查的是引用是否相等 - 这是两个不同的实例意味着false。执行此操作后，比较时还应使用recordInDB.Equals(recordInXML)

执行此操作后，您还可以重构一下：

var keepList = recordInDB.Where(record => Graph.AddressList.Contains(record));
var removeList = updateAddressList.Except(keepList).ToList();
foreach (Address record in removeList)
{                                           
    DbContext.AddressList.DeleteObject(record);
}

使用选项3，然后在Address_0006中实施IEquatable<Address>：

public class Address_0006 : IEquatable<Address>
{
    public bool Equals(Address other)
    {
        // Compare here that each of the relevant properties in this (Address_0006) 
        // equals the corresponding property in other (Address)
    }
}

Answer 2

您可以反映Address和Address_0006类型的属性，并检查同名命名的属性是否包含相同的数据。但是反射速度相当慢，所以除非你有数百个属性并经常更改，否则我建议手动编写比较。

比较两个对象的值而不列出每一列

2 个答案: