Entity Framework Multiple Column as Primary Key by Fluent Api
50,639
Use anonymous type object instead of 2 separated statements:
HasKey(pc => new { pc.ProductId, pc.CategoryId });
From Microsoft Docs: EntityTypeConfiguration.HasKey Method
If the primary key is made up of multiple properties then specify an anonymous type including the properties. For example, in C#
t => new { t.Id1, t.Id2 }
and in Visual Basic .NetFunction(t) New With { t.Id1, t.Id2 }
.
Author by
Barış Velioğlu
Updated on March 31, 2021Comments
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Barış Velioğlu about 3 years
These are my simplified domain classes.
public class ProductCategory { public int ProductId { get; set; } public int CategoryId { get; set; } public virtual Product Product { get; set; } public virtual Category Category { get; set; } } public class Product { public int Id { get; set; } public string Name { get; set; } } public class Category { public int Id { get; set; } public string Name { get; set; } public int? ParentCategoryId { get; set;} }
This is my mapping class. But it doesn't work.
public class ProductCategoryMap : EntityTypeConfiguration<ProductCategory> { public ProductCategoryMap() { ToTable("ProductCategory"); HasKey(pc => pc.ProductId); HasKey(pc => pc.CategoryId); } }
How should I map these classes to provide, so that one product can be seen in multiple categories?
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Alicia about 4 yearsFor me, in VB.NET, it was
Function(t) With { t.Id1, t.id2 }
that did the trick (rather than "From"). -
zolty13 almost 4 yearsIs it possible to convert non-primitive value object containing two fields? :
public class MyId { public int CompanyId; public int UserId }
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ilyas varol over 2 yearsThanks to you, I learned this usage. Before I searched a lot time but I got nothing about this. By the way, is it called AlternateKey as well?