简单的T4生成简单POCO

Question

我正在寻找一个教程,指导或软件,可以为ASP.NET MVC中的某些SQL Server表生成简单的POCO.像这样的东西:

1)保留SQL Server数据库中应该生成POCO的表名列表

2)将列表提供给某个程序

3)程序在单个.cs文件中生成一个简单的POCO(更像是DTO),或附加到Poco.cs. 无论哪种方式,都没关系.

例如:

public class MyDto
{
    public int Id { get; set; }
    public string Name { get; set; }
    public bool? IsMale {get; set;}
}

4)每当我想重新生成POCO时运行程序

该程序可能是WinForm,命令行或其他东西.没关系.

Answer 1

我想回答这个问题但很忙.

我已经创建了一个关于如何读取数据库模式并从中生成类和属性的简单示例.

基本上你应该能够把它切成TT文件(参见Oleg Sychs博客,了解如何开始),更新连接字符串并保存以执行模板.

我并不认为这是一个完整的样本,但它可以作为您的起点:

  <#@ template   language    = "C#"                           #>
  <#@ assembly   name        = "Microsoft.CSharp"             #>
  <#@ assembly   name        = "System.Core"                  #>
  <#@ assembly   name        = "System.Data"                  #>
  <#@ import     namespace   = "System.Collections.Generic"   #>
  <#@ import     namespace   = "System.Dynamic"               #>
  <#@ import     namespace   = "System.Linq"                  #>
  <#@ import     namespace   = "System.Data.SqlClient"        #>

  <#
     var namespaceName    = "Poco2";
     // Update the connection string to something appropriate
     var connectionString = @"Data Source=localhost\SQLExpress;Initial Catalog=MyTest;Integrated Security=True";
  #>

  <#
     using (var db = new SqlConnection (connectionString))
     using (var cmd = db.CreateCommand ())
     {
        db.Open();
        var tables              = ReadRows (cmd, "SELECT * FROM sys.tables").ToArray ();

        var columns             = ReadRows (cmd, "SELECT * FROM sys.columns").ToLookup (k => k.object_id);

        var indexes             = ReadRows (cmd, "SELECT * FROM sys.indexes").ToLookup (k => k.object_id);
        var indexColumns        = ReadRows (cmd, "SELECT * FROM sys.index_columns").ToLookup (k => k.object_id);

        var foreignKeys         = ReadRows (cmd, "SELECT * FROM sys.foreign_keys").ToArray ();
        var foreignKeyColumns   = ReadRows (cmd, "SELECT * FROM sys.foreign_key_columns").ToArray ();
  #>
  namespace <#=namespaceName#>
  {
     using System;
     using System.Data.Linq.Mapping;

  <#
        foreach (var table in tables)
        {         
  #>
     [Table]
     partial class <#=table.name#>
     {
  <#
           IEnumerable<dynamic> tc = columns[table.object_id];
           var tableColumns = tc.OrderBy (r => r.column_id).ToArray ();          

           IEnumerable<dynamic> ti = indexes[table.object_id];
           var tableIndexes = ti.ToArray ();          

           var primaryKeyIndex = tableIndexes.FirstOrDefault (i => i.is_primary_key);
           var primaryKeyColumns = new Dictionary<dynamic, dynamic> ();
           if (primaryKeyIndex != null)
           {
              IEnumerable<dynamic> pc = indexColumns[table.object_id];
              primaryKeyColumns = pc
                 .Where (c => c.index_id == primaryKeyIndex.index_id)
                 .ToDictionary (c => c.column_id, c => c.key_ordinal)
                 ;
           }

           foreach (var tableColumn in tableColumns)
           {
              var type = MapToType (tableColumn.user_type_id, tableColumn.max_length, tableColumn.is_nullable);

  #>
        [Column (IsPrimaryKey = <#=primaryKeyColumns.ContainsKey (tableColumn.column_id) ? "true" : "false"#>)]
        public <#=type#> <#=tableColumn.name#> {get;set;}

  <#
           }
  #>

     }
  <#
        }
  #>
  }
  <#
     }
  #>

  <#+

     struct DataType
     {     
        public readonly int     SizeOf;
        public readonly string  SingularType;
        public readonly string  PluralType;

        public DataType (
           int sizeOf,
           string singularType,
           string pluralType = null
           )
        {
           SizeOf         = sizeOf;
           SingularType   = singularType;
           PluralType     = pluralType ?? (singularType + "[]");
        }

     }
     static Dictionary<int, DataType> dataTypes = new Dictionary<int, DataType>
        {
           {61   , new DataType (8,  "DateTime"            )},
           {127  , new DataType (8,  "long"                )},
           {165  , new DataType (1,  "byte"                )},
           {231  , new DataType (2,  "char"    ,  "string" )},
        };

     static string MapToType (int typeId, int maxLength, bool isNullable)
     {
        DataType dataType;

        if (dataTypes.TryGetValue (typeId, out dataType))
        {
           var length = maxLength > 0 ? (maxLength / dataType.SizeOf) : int.MaxValue;
           if (length > 1)
           {
              return dataType.PluralType;
           }
           else
           {
              return dataType.SingularType + (isNullable ? "?" : "");
           }
        }
        else
        {
           return "UnknownType_"+ typeId;
        }
     }

     static IEnumerable<dynamic> ReadRows (SqlCommand command, string sql)
     {
        command.CommandText = sql ?? "";

        using (var reader = command.ExecuteReader())
        {
           while (reader.Read())
           {
              var dyn = new ExpandoObject ();
              IDictionary<string, object> dic = dyn;

              for (var iter = 0; iter < reader.FieldCount; ++iter)
              {
                    dic[reader.GetName(iter) ?? ""] = reader.GetValue(iter);
              }

              yield return dyn;
           }

        }
     }


  #>