blocks|key|1620814|text|如果添加NotMapped属性，实体框架将不会为其创建列。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1620815|using+System.ComponentModel.DataAnnotations.Schema;

namespace+DomainModel
{
++++public+partial+class+Customer
++++{
++++++++public+int+Id+{+get;+set;+}

++++++++public+string+Name+{+get;+set;+}

++++++++[NotMapped]
++++++++public+string+FullName+{+get;+set;+}
++++}
}|code-block|syntax|javascript|1620816|或者，如果您想映射列，但在某些数据库中它已经存在，这里有一个迁移，它将仅在列不存在时添加该列。|1620817|namespace+DataAccess.Migrations
{
++++using+System;
++++using+System.Data.Entity.Migrations;
++++
++++public+partial+class+AddFullNameToCustomer+:+DbMigration
++++{
++++++++public+override+void+Up()
++++++++{
++++++++++++Sql(@"IF+COL_LENGTH('Customer',+'FullName')+IS+NULL
++++++++++++BEGIN
++++++++++++++++ALTER+TABLE+Customer
++++++++++++++++ADD+[FullName]+varchar(200)+null
++++++++++++END");
++++++++}
++++++++
++++++++public+override+void+Down()
++++++++{
++++++++}
++++}
}|1620818|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

If you add the [NotMapped] attribute, entity framework will not create a column for it.
<pre><code>using System.ComponentModel.DataAnnotations.Schema;

namespace DomainModel
{
 public partial class Customer
 {
 public int Id { get; set; }

 public string Name { get; set; }

 [NotMapped]
 public string FullName { get; set; }
 }
}
</code></pre>
Or if you want to map the column, but in some databases it already exists, here's a migration which will add the column only if it does not exist.
<pre><code>namespace DataAccess.Migrations
{
 using System;
 using System.Data.Entity.Migrations;
 
 public partial class AddFullNameToCustomer : DbMigration
 {
 public override void Up()
 {
 Sql(@&quot;IF COL_LENGTH('Customer', 'FullName') IS NULL
 BEGIN
 ALTER TABLE Customer
 ADD [FullName] varchar(200) null
 END&quot;);
 }
 
 public override void Down()
 {
 }
 }
}
</code></pre>

blocks|key|1610701|text|addYou需要添加NotMapped属性|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1610702|使用System.ComponentModel.DataAnnotations.Schema；|1610703|namespace+DomainModel
{
++++public+partial+class+Customer
++++{
++++++++public+int+Id+{+get;+set;+}

++++++++public+string+Name+{+get;+set;+}

++++++++[NotMapped]
++++++++public+string+FullName+{+get;+set;+}
++++}
}|code-block|syntax|javascript|1610704|有些人喜欢Model类非常干净--没有任何数据注释。他们更喜欢在DataContext类中完成配置。您可以在class属性上使用Ignore方法，以防止它映射到数据库列。|1610705|protected+override+void+OnModelCreating(DbModelBuilder+modelBuilder)
++++++++{
++++++++++++modelBuilder.Entity<Customer>().Ignore(customer+=>+customer.FullName);
++++++++++++base.OnModelCreating(modelBuilder);
++++++++}|1610706|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|P|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|Q|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|R|8|@]|9|@]|A|$]]|$1|K|3|L|5|F|7|S|8|@]|9|@]|A|$G|H]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

addYou need to Add the [NotMapped] attribute 
using System.ComponentModel.DataAnnotations.Schema;
<pre><code>namespace DomainModel
{
 public partial class Customer
 {
 public int Id { get; set; }

 public string Name { get; set; }

 [NotMapped]
 public string FullName { get; set; }
 }
}
</code></pre>
Some prefer Model classes to be very clean – without any Data Annotations. They prefer the configuration to be done DataContext class.
You can use the Ignore method on the class property to prevent it from mapping to the database column.
<pre><code>protected override void OnModelCreating(DbModelBuilder modelBuilder)
 {
 modelBuilder.Entity&lt;Customer&gt;().Ignore(customer =&gt; customer.FullName);
 base.OnModelCreating(modelBuilder);
 }
</code></pre>

blocks|key|1610723|text|Just+stop+it。你在为自己创造一个痛苦的世界。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1610724|如果你想拥有一个动态的模式，那么你根本就不应该使用实体框架。|style|BOLD|1610725|通过创建一个迁移，确保在每个数据库中创建字段(以便在运行时，上下文始终与数据库匹配)，并确保在应用程序运行之前执行迁移，从而简化并避免所有这些令人头疼的问题。|1610726|entityMap|0|LINK|mutability|MUTABLE|url|https://www.youtube.com/watch?v=Ow0lr63y4Mw^0|0|C|0|0|0|T|0|0^^$0|@$1|2|3|4|5|6|7|R|8|@]|9|@$A|S|B|T|1|U]]|C|$]]|$1|D|3|E|5|6|7|V|8|@$A|W|B|X|F|G]]|9|@]|C|$]]|$1|H|3|I|5|6|7|Y|8|@]|9|@]|C|$]]|$1|J|3|-4|5|6|7|Z|8|@]|9|@]|C|$]]]|K|$L|$5|M|N|O|C|$P|Q]]]]

<a href="https://www.youtube.com/watch?v=Ow0lr63y4Mw" rel="nofollow noreferrer">Just stop it</a>. You're creating a world of pain for yourself.
If you want to have a dynamic schema, then you shouldn't be using Entity Framework at all.
Simplify and avoid all this headache by creating a migration that ensures that the field gets created in every single database (so that at runtime, the context will always match the database) and make sure the migration is executed before the app runs.

I have added new property in my Entity Model as the new column has got added in DB table. But In that column might or might be there in other client database. So, How handle this? I have tried <code>modelBuilder.Entity&lt;Customer&gt;().Ignore(customer =&gt; customer.FullName);</code>
But it's not ignoring the property in entity. Because we have entity mapped class so it is not ignoring it.
Solution please?

Exclude or Ignore Property of an Entity model if column is not exist in database table

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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我已经在我的实体模型中添加了新属性，因为新列已添加到DB表中。但是在该列中可能在其他客户端数据库中，也可能在其他客户端数据库中。那么，如何处理这个问题呢？我尝试过modelBuilder.Entity<Customer>().Ignore(customer => customer.FullName);，但它并没有忽略e...

问如果数据库表中不存在列，则排除或忽略实体模型的属性
EN

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问如果数据库表中不存在列，则排除或忽略实体模型的属性EN