C# 将modelBuilder配置为一次组合多个属性配置
是否有一种方法可以为Required、MaxLength和HasColumn组合多个属性,或者需要为每个属性创建一个属性 我希望能够包括多个需要的字段,如果它们是相同的MaxLength,则将其分配给它们,而不是像我现在所做的那样为实体中的每个字段创建一个新字段C# 将modelBuilder配置为一次组合多个属性配置,c#,entity-framework,C#,Entity Framework,是否有一种方法可以为Required、MaxLength和HasColumn组合多个属性,或者需要为每个属性创建一个属性 我希望能够包括多个需要的字段,如果它们是相同的MaxLength,则将其分配给它们,而不是像我现在所做的那样为实体中的每个字段创建一个新字段 public class DataEntryContext : DbContext { public DataEntryContext(DbContextOptions<DataEntryContext> optio
public class DataEntryContext : DbContext
{
public DataEntryContext(DbContextOptions<DataEntryContext> options)
:base (options)
{ }
public DbSet<Employee> Employees { get; set; }
public DbSet<Department> Departments { get; set; }
protected override void OnModelCreating(ModelBuilder modelBuilder)
{
modelBuilder.Entity<Employee>()
.HasKey(e => e.EmpId);
modelBuilder.Entity<Employee>()
.Property(e => e.EmpFirstName)
.HasColumnType("varchar(50)")
.HasMaxLength(50)
.IsRequired();
modelBuilder.Entity<Employee>()
.Property(e => e.EmpLastName)
.HasColumnType("varchar(50)")
.HasMaxLength(50)
.IsRequired();
modelBuilder.Entity<Employee>()
.Property(e => e.EmpPhoneNumber)
.HasColumnType("varchar(10)")
.HasMaxLength(10)
.IsRequired();
modelBuilder.Entity<Employee>()
.Property(e => e.EmpStartDate)
.HasColumnType("datetime")
.IsRequired();
modelBuilder.Entity<Department>()
.HasKey(d => d.DeptId);
modelBuilder.Entity<Department>()
.Property(d => d.DeptName)
.HasColumnType("varchar(50)")
.HasMaxLength(50)
.IsRequired();
}
}
公共类DataEntryContext:DbContext
{
公共DataEntryContext(DbContextOptions)
:基本(选项)
{ }
公共数据库集雇员{get;set;}
公共数据库集部门{get;set;}
模型创建时受保护的覆盖无效(ModelBuilder ModelBuilder)
{
modelBuilder.Entity()
.HasKey(e=>e.EmpId);
modelBuilder.Entity()
.Property(e=>e.EmpFirstName)
.HasColumnType(“varchar(50)”)
.HasMaxLength(50)
.IsRequired();
modelBuilder.Entity()
.Property(e=>e.EmpLastName)
.HasColumnType(“varchar(50)”)
.HasMaxLength(50)
.IsRequired();
modelBuilder.Entity()
.Property(e=>e.EmpPhoneNumber)
.HasColumnType(“varchar(10)”)
.HasMaxLength(10)
.IsRequired();
modelBuilder.Entity()
.Property(e=>e.EmpStartDate)
.HasColumnType(“日期时间”)
.IsRequired();
modelBuilder.Entity()
.HasKey(d=>d.DeptId);
modelBuilder.Entity()
.Property(d=>d.DeptName)
.HasColumnType(“varchar(50)”)
.HasMaxLength(50)
.IsRequired();
}
}
不,目前还不可能。你必须为每一处房产写上这句话。您最多可以强制Entity Framework将.Net数据类型映射到特定的MS SQL数据类型,如图所示。当然可以,您只需自己编写代码即可。例如,我编写了一个
EntityTypeConfigurationExtensions
,它允许您在一次调用中使用多个属性配置实体,而不是多次调用。我不明白为什么您不能修改我的代码以使用params
,然后您可以传递多个属性:
(必须先进行propertyConfiguration,然后再进行propertyExpression)
使用字符串varchar50=“varchar(50)”;并使用modelBuilder.Entity().Property(d=>d.DeptName).HasColumnType(varchar50).HasMaxLength(50).IsRequired();这样的尝试往往会降低代码的灵活性。有一个不一致,一个最大长度为10(而不是50)的必填字段。您将如何处理?感谢您的回复,但我想知道,如果可能的话,如何在一个实体中只调用一次就包含多个字段。也许我解释得不对。请看我想知道的是可能还是不可能<代码>modelBuilder.Entity().Property(e=>e.EmpFirstName),(e=>e.EmpLastName).HasColumnType(“varchar(50)”).IsRequired()代码>
public static class EntityTypeConfigurationExtensions
{
public static EntityTypeConfiguration<TEntityType> Property<TEntityType>(
this EntityTypeConfiguration<TEntityType> instance,
Expression<Func<TEntityType, byte[]>> propertyExpression,
Func<BinaryPropertyConfiguration, BinaryPropertyConfiguration> propertyConfiguration)
where TEntityType : class
{
propertyConfiguration(instance.Property(propertyExpression));
return instance;
}
public static EntityTypeConfiguration<TEntityType> Property<TEntityType>(
this EntityTypeConfiguration<TEntityType> instance,
Expression<Func<TEntityType, Guid>> propertyExpression,
Func<PrimitivePropertyConfiguration, PrimitivePropertyConfiguration> propertyConfiguration)
where TEntityType : class
{
propertyConfiguration(instance.Property(propertyExpression));
return instance;
}
public static EntityTypeConfiguration<TEntityType> Property<TEntityType>(
this EntityTypeConfiguration<TEntityType> instance,
Expression<Func<TEntityType, Guid?>> propertyExpression,
Func<PrimitivePropertyConfiguration, PrimitivePropertyConfiguration> propertyConfiguration)
where TEntityType : class
{
propertyConfiguration(instance.Property(propertyExpression));
return instance;
}
public static EntityTypeConfiguration<TEntityType> Property<TEntityType>(
this EntityTypeConfiguration<TEntityType> instance,
Expression<Func<TEntityType, TimeSpan?>> propertyExpression,
Func<DateTimePropertyConfiguration, DateTimePropertyConfiguration> propertyConfiguration)
where TEntityType : class
{
propertyConfiguration(instance.Property(propertyExpression));
return instance;
}
public static EntityTypeConfiguration<TEntityType> Property<TEntityType>(
this EntityTypeConfiguration<TEntityType> instance,
Expression<Func<TEntityType, TimeSpan>> propertyExpression,
Func<DateTimePropertyConfiguration, DateTimePropertyConfiguration> propertyConfiguration)
where TEntityType : class
{
propertyConfiguration(instance.Property(propertyExpression));
return instance;
}
public static EntityTypeConfiguration<TEntityType> Property<TEntityType>(
this EntityTypeConfiguration<TEntityType> instance,
Expression<Func<TEntityType, DateTimeOffset?>> propertyExpression,
Func<DateTimePropertyConfiguration, DateTimePropertyConfiguration> propertyConfiguration)
where TEntityType : class
{
propertyConfiguration(instance.Property(propertyExpression));
return instance;
}
public static EntityTypeConfiguration<TEntityType> Property<TEntityType>(
this EntityTypeConfiguration<TEntityType> instance,
Expression<Func<TEntityType, DateTimeOffset>> propertyExpression,
Func<DateTimePropertyConfiguration, DateTimePropertyConfiguration> propertyConfiguration)
where TEntityType : class
{
propertyConfiguration(instance.Property(propertyExpression));
return instance;
}
public static EntityTypeConfiguration<TEntityType> Property<TEntityType>(
this EntityTypeConfiguration<TEntityType> instance,
Expression<Func<TEntityType, DateTime?>> propertyExpression,
Func<DateTimePropertyConfiguration, DateTimePropertyConfiguration> propertyConfiguration)
where TEntityType : class
{
propertyConfiguration(instance.Property(propertyExpression));
return instance;
}
public static EntityTypeConfiguration<TEntityType> Property<TEntityType>(
this EntityTypeConfiguration<TEntityType> instance,
Expression<Func<TEntityType, DateTime>> propertyExpression,
Func<DateTimePropertyConfiguration, DateTimePropertyConfiguration> propertyConfiguration)
where TEntityType : class
{
propertyConfiguration(instance.Property(propertyExpression));
return instance;
}
public static EntityTypeConfiguration<TEntityType> Property<TEntityType>(
this EntityTypeConfiguration<TEntityType> instance,
Expression<Func<TEntityType, decimal?>> propertyExpression,
Func<DecimalPropertyConfiguration, DecimalPropertyConfiguration> propertyConfiguration)
where TEntityType : class
{
propertyConfiguration(instance.Property(propertyExpression));
return instance;
}
public static EntityTypeConfiguration<TEntityType> Property<TEntityType>(
this EntityTypeConfiguration<TEntityType> instance,
Expression<Func<TEntityType, decimal>> propertyExpression,
Func<DecimalPropertyConfiguration, DecimalPropertyConfiguration> propertyConfiguration)
where TEntityType : class
{
propertyConfiguration(instance.Property(propertyExpression));
return instance;
}
public static EntityTypeConfiguration<TEntityType> Property<TEntityType>(
this EntityTypeConfiguration<TEntityType> instance,
Expression<Func<TEntityType, string>> propertyExpression,
Func<StringPropertyConfiguration, StringPropertyConfiguration> propertyConfiguration)
where TEntityType : class
{
propertyConfiguration(instance.Property(propertyExpression));
return instance;
}
}
modelBuilder.Entity<Employee>()
.HasKey(e => e.EmpId);
modelBuilder.Entity<Employee>()
.Property(e => e.EmpFirstName)
.HasColumnType("varchar(50)")
.HasMaxLength(50)
.IsRequired();
modelBuilder.Entity<Employee>()
.Property(e => e.EmpLastName)
.HasColumnType("varchar(50)")
.HasMaxLength(50)
.IsRequired();
modelBuilder.Entity<Employee>()
.Property(e => e.EmpStartDate)
.HasColumnType("datetime")
.IsRequired();
modelBuilder.Entity<Employee>()
.HasKey(e => e.EmpId)
.Property(e => e.EmpFirstName,
p => p.HasColumnType("varchar(50)")
.HasMaxLength(50)
.IsRequired())
.Property(e => e.EmpLastName,
p => p.HasColumnType("varchar(50)")
.HasMaxLength(50)
.IsRequired())
.Property(e => e.EmpStartDate,
p => p.HasColumnType("datetime")
.IsRequired());
modelBuilder.Entity<Employee>()
.HasKey(e => e.EmpId)
.Property(p => p.HasColumnType("varchar(50)")
.HasMaxLength(50)
.IsRequired(),
e => e.EmpFirstName,
e => e.EmpLastName);
.Property(p => p.HasColumnType("datetime")
.IsRequired(),
e => e.EmpStartDate,);