我是ASP / EF的新手。我在我的個人項目中使用ASP 5和Entity Framework 7。
所以我能夠使用代碼優先方法創建數據庫和表,但是所有表名都是單數的,默認情況下不會復數。
在我的ServerMatrixDemoDB DbContext文件中,我在DBSets下面創建了:
public class ServerMatrixDemoDB : DbContext
{
public ServerMatrixDemoDB()
{
Database.EnsureCreated();
}
public DbSet<Domain> Domains { get; set; }
public DbSet<Environment> Environments { get; set; }
public DbSet<Network> Networks { get; set; }
public DbSet<OsVersion> OsVersions { get; set; }
public DbSet<Tier> Tiers { get; set; }
public DbSet<Service> Services { get; set; }
public DbSet<HardwareType> HardwareTypes { get; set; }
public DbSet<Powershell> Powershell { get; set; }
public DbSet<DotNetVersion> DotNetVersions { get; set; }
public DbSet<Status> Status { get; set; }
public DbSet<Servers> Servers { get; set; }
public DbSet<Application> Applications { get; set; }
}
在我的startup.cs文件中,我使用下面的代碼:
public void ConfigureServices(IServiceCollection services)
{
services.AddMvc() // Add MVC Dependency.
.AddJsonOptions(
opt =>
{
opt.SerializerSettings.ContractResolver = new CamelCasePropertyNamesContractResolver(); // Api convert all property names to CamelCase.
}
);
services.AddLogging(); // Enable Logging for database errors.
services.AddEntityFramework()
.AddSqlServer()
.AddDbContext<ServerMatrixDemoDB>(options =>
{
options.UseSqlServer(@"Server=.\SQLEXPRESS;user id=sa;password='passwrd';Database=ServerMatrixDemoDB;integrated security=True;");
});
services.AddTransient<ServerMatrixDemoSeedData>();
}
一旦我構建並運行項目,就會創建一個數據庫和表,但所有表名都是單數。有沒有辦法在代碼第一種方法中復數表名?
您可以在OnModelCreating重載中執行此操作,如 -
protected override void OnModelCreating(ModelBuilder modelBuilder)
{
foreach (var entity in modelBuilder.Model.GetEntityTypes())
{
modelBuilder.Entity(entity.Name).ToTable(entity.Name + "s");
}
}
您也可以使用“數據註釋”來完成此操作
[Table("blogs")]
public class Blog
{
public int BlogId { get; set; }
public string Url { get; set; }
}
或流利的Api
class MyContext : DbContext
{
public DbSet<Blog> Blogs { get; set; }
protected override void OnModelCreating(ModelBuilder modelBuilder)
{
modelBuilder.Entity<Blog>()
.ToTable("blogs");
}
}
有關詳細信息,請參閱 - EF7的文檔
當前代碼將tables
, properties
, keys
和indexes
轉換為Postgre
snake case,您可以將它用作自定義約定的基礎:
using System;
using System.Text.RegularExpressions;
using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.Metadata;
using Npgsql;
namespace Database.Customization
{
public class PostgreDbContext : DbContext
{
private static readonly Regex _keysRegex = new Regex("^(PK|FK|IX)_", RegexOptions.Compiled);
public PostgreDbContext(DbContextOptions options)
: base(options)
{
}
protected override void OnModelCreating(ModelBuilder modelBuilder)
{
base.OnModelCreating(modelBuilder);
FixSnakeCaseNames(modelBuilder);
}
private void FixSnakeCaseNames(ModelBuilder modelBuilder)
{
var mapper = new NpgsqlSnakeCaseNameTranslator();
foreach (var table in modelBuilder.Model.GetEntityTypes())
{
ConvertToSnake(mapper, table);
foreach (var property in table.GetProperties())
{
ConvertToSnake(mapper, property);
}
foreach (var primaryKey in table.GetKeys())
{
ConvertToSnake(mapper, primaryKey);
}
foreach (var foreignKey in table.GetForeignKeys())
{
ConvertToSnake(mapper, foreignKey);
}
foreach (var indexKey in table.GetIndexes())
{
ConvertToSnake(mapper, indexKey);
}
}
}
private void ConvertToSnake(INpgsqlNameTranslator mapper, object entity)
{
switch (entity)
{
case IMutableEntityType table:
var relationalTable = table.Relational();
relationalTable.TableName = ConvertGeneralToSnake(mapper, relationalTable.TableName);
if (relationalTable.TableName.StartsWith("asp_net_"))
{
relationalTable.TableName = relationalTable.TableName.Replace("asp_net_", string.Empty);
relationalTable.Schema = "identity";
}
break;
case IMutableProperty property:
property.Relational().ColumnName = ConvertGeneralToSnake(mapper, property.Relational().ColumnName);
break;
case IMutableKey primaryKey:
primaryKey.Relational().Name = ConvertKeyToSnake(mapper, primaryKey.Relational().Name);
break;
case IMutableForeignKey foreignKey:
foreignKey.Relational().Name = ConvertKeyToSnake(mapper, foreignKey.Relational().Name);
break;
case IMutableIndex indexKey:
indexKey.Relational().Name = ConvertKeyToSnake(mapper, indexKey.Relational().Name);
break;
default:
throw new NotImplementedException("Unexpected type was provided to snake case converter");
}
}
private string ConvertKeyToSnake(INpgsqlNameTranslator mapper, string keyName) =>
ConvertGeneralToSnake(mapper, _keysRegex.Replace(keyName, match => match.Value.ToLower()));
private string ConvertGeneralToSnake(INpgsqlNameTranslator mapper, string entityName) =>
mapper.TranslateMemberName(ModifyNameBeforeConvertion(mapper, entityName));
protected virtual string ModifyNameBeforeConvertion(INpgsqlNameTranslator mapper, string entityName) => entityName;
}
}