如何按慣例首先刪除代碼中的下劃線外鍵字段

code-first entity-framework entity-framework-6 naming-conventions

我的項目中有多個課程(包括TPT)。每個POCO都有一個BaseClass ,它有一個GUID (稱為GlobalKey )作為主鍵。

首先,我使用DataAnnotations創建正確的外鍵。但是我在將對應的GUID與對象本身同步時遇到了問題。

現在我想只有一個虛擬導航屬性,以便數據庫中的GUID字段由NamingConvention創建。但是字段名稱總是添加一個下劃線,後跟單詞GlobalKey (這是正確的)。當我想刪除下劃線時,我不想通過流暢的API通過我的所有POCO來執行此操作:

// Remove underscore from Navigation-Field     
modelBuilder.Entity<Person>()
            .HasOptional(x => x.Address)
            .WithMany()
            .Map(a => a.MapKey("AddressGlobalKey"));

是否有任何想法通過覆蓋慣例為所有POCOS做到這一點?

提前致謝。

安德烈亞斯

一般承認的答案

我終於通過編寫自定義約定找到了答案。此約定適用於EF 6.0 RC1(上週的代碼),因此我認為在EF 6.0發布後它可能會繼續工作。

使用此方法,標準EF約定標識獨立關聯(IAs),然後為外鍵字段創建EdmProperty。然後,此約定出現並重命名外鍵字段。

/// <summary>
/// Provides a convention for fixing the independent association (IA) foreign key column names.
/// </summary>
public class ForeignKeyNamingConvention : IStoreModelConvention<AssociationType>
{

    public void Apply(AssociationType association, DbModel model)
    {
        // Identify a ForeignKey properties (including IAs)
        if (association.IsForeignKey)
        {
            // rename FK columns
            var constraint = association.Constraint;
            if (DoPropertiesHaveDefaultNames(constraint.FromProperties, constraint.ToRole.Name, constraint.ToProperties))
            {
                NormalizeForeignKeyProperties(constraint.FromProperties);
            }
            if (DoPropertiesHaveDefaultNames(constraint.ToProperties, constraint.FromRole.Name, constraint.FromProperties))
            {
                NormalizeForeignKeyProperties(constraint.ToProperties);
            }
        }
    }

    private bool DoPropertiesHaveDefaultNames(ReadOnlyMetadataCollection<EdmProperty> properties, string roleName, ReadOnlyMetadataCollection<EdmProperty> otherEndProperties)
    {
        if (properties.Count != otherEndProperties.Count)
        {
            return false;
        }

        for (int i = 0; i < properties.Count; ++i)
        {
            if (!properties[i].Name.EndsWith("_" + otherEndProperties[i].Name))
            {
                return false;
            }
        }
        return true;
    }

    private void NormalizeForeignKeyProperties(ReadOnlyMetadataCollection<EdmProperty> properties)
    {
        for (int i = 0; i < properties.Count; ++i)
        {
            string defaultPropertyName = properties[i].Name;
            int ichUnderscore = defaultPropertyName.IndexOf('_');
            if (ichUnderscore <= 0)
            {
                continue;
            }
            string navigationPropertyName = defaultPropertyName.Substring(0, ichUnderscore);
            string targetKey = defaultPropertyName.Substring(ichUnderscore + 1);

            string newPropertyName;
            if (targetKey.StartsWith(navigationPropertyName))
            {
                newPropertyName = targetKey;
            }
            else
            {
                newPropertyName = navigationPropertyName + targetKey;
            }
            properties[i].Name = newPropertyName;
        }
    }

}

請注意,在DbContext.OnModelCreating覆蓋中, DbContext “約定”添加到DbContext中,使用:

/// <summary>
/// Provides a convention for fixing the independent association (IA) foreign key column names.
/// </summary>
public class ForeignKeyNamingConvention : IStoreModelConvention<AssociationType>
{

    public void Apply(AssociationType association, DbModel model)
    {
        // Identify a ForeignKey properties (including IAs)
        if (association.IsForeignKey)
        {
            // rename FK columns
            var constraint = association.Constraint;
            if (DoPropertiesHaveDefaultNames(constraint.FromProperties, constraint.ToRole.Name, constraint.ToProperties))
            {
                NormalizeForeignKeyProperties(constraint.FromProperties);
            }
            if (DoPropertiesHaveDefaultNames(constraint.ToProperties, constraint.FromRole.Name, constraint.FromProperties))
            {
                NormalizeForeignKeyProperties(constraint.ToProperties);
            }
        }
    }

    private bool DoPropertiesHaveDefaultNames(ReadOnlyMetadataCollection<EdmProperty> properties, string roleName, ReadOnlyMetadataCollection<EdmProperty> otherEndProperties)
    {
        if (properties.Count != otherEndProperties.Count)
        {
            return false;
        }

        for (int i = 0; i < properties.Count; ++i)
        {
            if (!properties[i].Name.EndsWith("_" + otherEndProperties[i].Name))
            {
                return false;
            }
        }
        return true;
    }

    private void NormalizeForeignKeyProperties(ReadOnlyMetadataCollection<EdmProperty> properties)
    {
        for (int i = 0; i < properties.Count; ++i)
        {
            string defaultPropertyName = properties[i].Name;
            int ichUnderscore = defaultPropertyName.IndexOf('_');
            if (ichUnderscore <= 0)
            {
                continue;
            }
            string navigationPropertyName = defaultPropertyName.Substring(0, ichUnderscore);
            string targetKey = defaultPropertyName.Substring(ichUnderscore + 1);

            string newPropertyName;
            if (targetKey.StartsWith(navigationPropertyName))
            {
                newPropertyName = targetKey;
            }
            else
            {
                newPropertyName = navigationPropertyName + targetKey;
            }
            properties[i].Name = newPropertyName;
        }
    }

}

熱門答案

我知道這有點舊,但這裡有一個示例我如何通過我的流暢配置(OnModelCreating)指定映射列:

modelBuilder.Entity<Application>()
            .HasOptional(c => c.Account)
                .WithMany()
                .Map(c => c.MapKey("AccountId"));

希望這可以幫助,




許可下: CC-BY-SA with attribution
不隸屬於 Stack Overflow
這個KB合法嗎? 是的,了解原因
許可下: CC-BY-SA with attribution
不隸屬於 Stack Overflow
這個KB合法嗎? 是的,了解原因