Entity Framework Code First中有效的原始属性是什么？ [英] What are valid primitive properties in Entity Framework Code First?

问题描述

当我尝试将列映射到模型类中的char数据类型时，出现错误：

When I try to map a column to a char data type in my model class I get an error:

属性'[ ColumnName]不是类型 [ClassName]的
声明属性。
使用忽略方法或
NotMappedAttribute数据批注，确认
未将属性
明确从模型中排除。
确保它是有效的原始
属性。

The property '[ColumnName]' is not a declared property on type '[ClassName]'. Verify that the property has not been explicitly excluded from the model by using the Ignore method or NotMappedAttribute data annotation. Make sure that it is a valid primitive property.

EF代码有效的原始类型是什么？首先？

What are the valid primitive types for EF Code First?

推荐答案

这很有趣，但您实际上无法映射 char 属性。我刚刚检查了一下，如果您想在数据库中包含 char（1），则必须在下面使用 string 属性映射：

This is interesting but you really cannot map char property. I just checked it and if you want to have char(1) in the database you must use string property with following mapping:

modelBuilder.Entity<MyEntity>()
            .Property(p => p.MyProperty)
            .HasMaxLength(1)
            .IsFixedLength()
            .IsUnicode(false);

这不仅是代码优先的问题。这是整个EF的限制，因为EDMX设计器也不显示 char 类型。我认为允许的类型将与针对EDMX的CSDL参考中所述相同，因为代码首先只是包装器围绕相同的地图基础设施。

It is not only problem of Code-first. It is whole EF limitation because EDMX designer also doesn't show char type. I think allowed types will be same as described in CSDL reference for EDMX because code first is just wrapper around the same mapping infrastructure.

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