MVC中数据库表如果是一对一的主键关系时要加[Required]不然会出错Unable to determine the principal end of an association between the types

Unable to determine the principal end of an association between the types '***. The principal end of this association must be explicitly configured using either the relationship fluent API or data annotations.

 [Required]

 public virtual User User { get; set; }

解决的是如下情况：

Unable to determine the principal end of an association between the types '***. The principal end of this association must be explicitly configured using either the relationship fluent API or data annotations.的更多相关文章

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