使用T4模板生成POCO类

为什么叫T4？因为简写为4个T。

T4(Text Template Transformation Toolkit)是微软官方在VisualStudio 2008中开始使用的代码生成引擎。在 Visual Studio 中，“T4 文本模板”是由一些文本块和控制逻辑组成的混合模板，它可以生成文本文件。 在 Visual C# 或 Visual Basic 中，控制逻辑编写为程序代码的片段。生成的文件可以是任何类型的文本，例如网页、资源文件或任何语言的程序源代码。现在的VS中只要与代码生成相关的场景基本上都能找T4的身影，比如MVC的视图模板，Entity Framwork的DataContext模板等等。

若论灵活性，各种代码生成工具还真不如T4模板。

在VS2013种默认没有了T4模板，取而代之的是文本模板，但是他们的后缀名都是.tt。我们可以通过NuGet安装T4模板。

安装之后，我们在项目中新建项的时候，在VS模板中就多了两项和T4模板相关的模板。

当我们在新建的T4模板中进行代码编写的时候，默认是没有智能提示的，我们需要再安装一个T4Editor的VS插件tangibleT4EditorPlusModellingToolsVS2013.msi。

下载地址:

https://marketplace.visualstudio.com/items?itemName=tangibleengineeringGmbH.tangibleT4Editor230plusmodelingtoolsforVS2013

由于我这里用的是VS2013，所以按照13的插件，安装插件时先关闭VS，安装完成之后在T4模板中编写代码时就有了智能提示了。

关于T4模板的详细讲解，大家可以参照一下博客文章：

你必须懂的 T4 模板：体系架构

（译）理解 T4 模板：<#@ parameter #> 指令

我这里要说的是，如何在项目中替代其它的代码工具来使用，比如说，自动生成数据库中的POCO类。

思路：1、我们要查询中数据库中的表和字段。2、根据数据表名才，将其生成多个POCO类文件

How to do？

开发环境：VS2013

准备工作：添加必须的程序集引用

在自己电脑上面用everythin找到Microsoft.VisualStudio.TextTemplating.Interfaces.10.0.dll，然后添加引用，如果没有，你就网上下载一个。

方式一

1、添加一个T4模板文件DbHelper，将其后缀修改为.ttinclude，因为我是将其作为内嵌的T4文件，不修改扩展名的话，会将其当成T4模板文件进行生成。

<#+
    public class DbHelper
    {
        #region GetDbTables

        public static List<DbTable> GetDbTables(string connectionString, string database, string tables = null)
        {

            if (!string.IsNullOrEmpty(tables))
            {
                tables = string.Format(" and obj.name in ('{0}')", tables.Replace(",", "','"));
            }
            #region SQL
            string sql = string.Format(@"SELECT
                                    obj.name tablename,
                                    schem.name schemname,
                                    idx.rows,
                                    CAST
                                    (
                                        CASE
                                            WHEN (SELECT COUNT(1) FROM sys.indexes WHERE object_id= obj.OBJECT_ID AND is_primary_key=1) >=1 THEN 1
                                            ELSE 0
                                        END
                                    AS BIT) HasPrimaryKey
                                    from {0}.sys.objects obj
                                    inner join {0}.dbo.sysindexes idx on obj.object_id=idx.id and idx.indid<=1
                                    INNER JOIN {0}.sys.schemas schem ON obj.schema_id=schem.schema_id
                                    where type='U' {1}
                                    order by obj.name", database, tables);
            #endregion
            DataTable dt = GetDataTable(connectionString, sql);
            return dt.Rows.Cast<DataRow>().Select(row => new DbTable
            {
                TableName = row.Field<string>("tablename"),
                SchemaName = row.Field<string>("schemname"),
                Rows = row.Field<int>("rows"),
                HasPrimaryKey = row.Field<bool>("HasPrimaryKey")
            }).ToList();
        }
        #endregion

        #region GetDbColumns

        public static List<DbColumn> GetDbColumns(string connectionString, string database, string tableName, string schema = "dbo")
        {
            #region SQL
            string sql = string.Format(@"
                                    WITH indexCTE AS
                                    (
                                        SELECT
                                        ic.column_id,
                                        ic.index_column_id,
                                        ic.object_id
                                        FROM {0}.sys.indexes idx
                                        INNER JOIN {0}.sys.index_columns ic ON idx.index_id = ic.index_id AND idx.object_id = ic.object_id
                                        WHERE  idx.object_id =OBJECT_ID(@tableName) AND idx.is_primary_key=1
                                    )
                                    select
                                    colm.column_id ColumnID,
                                    CAST(CASE WHEN indexCTE.column_id IS NULL THEN 0 ELSE 1 END AS BIT) IsPrimaryKey,
                                    colm.name ColumnName,
                                    systype.name ColumnType,
                                    colm.is_identity IsIdentity,
                                    colm.is_nullable IsNullable,
                                    cast(colm.max_length as int) ByteLength,
                                    (
                                        case
                                            when systype.name='nvarchar' and colm.max_length>0 then colm.max_length/2
                                            when systype.name='nchar' and colm.max_length>0 then colm.max_length/2
                                            when systype.name='ntext' and colm.max_length>0 then colm.max_length/2
                                            else colm.max_length
                                        end
                                    ) CharLength,
                                    cast(colm.precision as int) Precision,
                                    cast(colm.scale as int) Scale,
                                    prop.value Remark
                                    from {0}.sys.columns colm
                                    inner join {0}.sys.types systype on colm.system_type_id=systype.system_type_id and colm.user_type_id=systype.user_type_id
                                    left join {0}.sys.extended_properties prop on colm.object_id=prop.major_id and colm.column_id=prop.minor_id
                                    LEFT JOIN indexCTE ON colm.column_id=indexCTE.column_id AND colm.object_id=indexCTE.object_id
                                    where colm.object_id=OBJECT_ID(@tableName)
                                    order by colm.column_id", database);
            #endregion
            SqlParameter param = new SqlParameter("@tableName", SqlDbType.NVarChar, ) { Value = string.Format("{0}.{1}.{2}", database, schema, tableName) };
            DataTable dt = GetDataTable(connectionString, sql, param);
            return dt.Rows.Cast<DataRow>().Select(row => new DbColumn()
            {
                ColumnID = row.Field<int>("ColumnID"),
                IsPrimaryKey = row.Field<bool>("IsPrimaryKey"),
                ColumnName = row.Field<string>("ColumnName"),
                ColumnType = row.Field<string>("ColumnType"),
                IsIdentity = row.Field<bool>("IsIdentity"),
                IsNullable = row.Field<bool>("IsNullable"),
                ByteLength = row.Field<int>("ByteLength"),
                CharLength = row.Field<int>("CharLength"),
                Scale = row.Field<int>("Scale"),
                Remark = row["Remark"].ToString()
            }).ToList();
        }

        #endregion     

        #region GetDataTable

        public static DataTable GetDataTable(string connectionString, string commandText, params SqlParameter[] parms)
        {
            using (SqlConnection connection = new SqlConnection(connectionString))
            {
                SqlCommand command = connection.CreateCommand();
                command.CommandText = commandText;
                command.Parameters.AddRange(parms);
                SqlDataAdapter adapter = new SqlDataAdapter(command);

                DataTable dt = new DataTable();
                adapter.Fill(dt);

                return dt;
            }
        }

        #endregion
    }

    #region DbTable
    /// <summary>
    /// 表结构
    /// </summary>
    public sealed class DbTable
    {
        /// <summary>
        /// 表名称
        /// </summary>
        public string TableName { get; set; }
        /// <summary>
        /// 表的架构
        /// </summary>
        public string SchemaName { get; set; }
        /// <summary>
        /// 表的记录数
        /// </summary>
        public int Rows { get; set; }

        /// <summary>
        /// 是否含有主键
        /// </summary>
        public bool HasPrimaryKey { get; set; }
    }
    #endregion

    #region DbColumn
    /// <summary>
    /// 表字段结构
    /// </summary>
    public sealed class DbColumn
    {
        /// <summary>
        /// 字段ID
        /// </summary>
        public int ColumnID { get; set; }

        /// <summary>
        /// 是否主键
        /// </summary>
        public bool IsPrimaryKey { get; set; }

        /// <summary>
        /// 字段名称
        /// </summary>
        public string ColumnName { get; set; }

        /// <summary>
        /// 字段类型
        /// </summary>
        public string ColumnType { get; set; }

        /// <summary>
        /// 数据库类型对应的C#类型
        /// </summary>
        public string CSharpType
        {
            get
            {
                return SqlServerDbTypeMap.MapCsharpType(ColumnType);
            }
        }

        /// <summary>
        ///
        /// </summary>
        public Type CommonType
        {
            get
            {
                return SqlServerDbTypeMap.MapCommonType(ColumnType);
            }
        }

        /// <summary>
        /// 字节长度
        /// </summary>
        public int ByteLength { get; set; }

        /// <summary>
        /// 字符长度
        /// </summary>
        public int CharLength { get; set; }

        /// <summary>
        /// 小数位
        /// </summary>
        public int Scale { get; set; }

        /// <summary>
        /// 是否自增列
        /// </summary>
        public bool IsIdentity { get; set; }

        /// <summary>
        /// 是否允许空
        /// </summary>
        public bool IsNullable { get; set; }

        /// <summary>
        /// 描述
        /// </summary>
        public string Remark { get; set; }
    }
    #endregion

    #region SqlServerDbTypeMap

    public class SqlServerDbTypeMap
    {
        public static string MapCsharpType(string dbtype)
        {
            if (string.IsNullOrEmpty(dbtype)) return dbtype;
            dbtype = dbtype.ToLower();
            string csharpType = "object";
            switch (dbtype)
            {
                case "bigint": csharpType = "long"; break;
                case "binary": csharpType = "byte[]"; break;
                case "bit": csharpType = "bool"; break;
                case "char": csharpType = "string"; break;
                case "date": csharpType = "DateTime"; break;
                case "datetime": csharpType = "DateTime"; break;
                case "datetime2": csharpType = "DateTime"; break;
                case "datetimeoffset": csharpType = "DateTimeOffset"; break;
                case "decimal": csharpType = "decimal"; break;
                case "float": csharpType = "double"; break;
                case "image": csharpType = "byte[]"; break;
                case "int": csharpType = "int"; break;
                case "money": csharpType = "decimal"; break;
                case "nchar": csharpType = "string"; break;
                case "ntext": csharpType = "string"; break;
                case "numeric": csharpType = "decimal"; break;
                case "nvarchar": csharpType = "string"; break;
                case "real": csharpType = "Single"; break;
                case "smalldatetime": csharpType = "DateTime"; break;
                case "smallint": csharpType = "short"; break;
                case "smallmoney": csharpType = "decimal"; break;
                case "sql_variant": csharpType = "object"; break;
                case "sysname": csharpType = "object"; break;
                case "text": csharpType = "string"; break;
                case "time": csharpType = "TimeSpan"; break;
                case "timestamp": csharpType = "byte[]"; break;
                case "tinyint": csharpType = "byte"; break;
                case "uniqueidentifier": csharpType = "Guid"; break;
                case "varbinary": csharpType = "byte[]"; break;
                case "varchar": csharpType = "string"; break;
                case "xml": csharpType = "string"; break;
                default: csharpType = "object"; break;
            }
            return csharpType;
        }

        public static Type MapCommonType(string dbtype)
        {
            if (string.IsNullOrEmpty(dbtype)) return Type.Missing.GetType();
            dbtype = dbtype.ToLower();
            Type commonType = typeof(object);
            switch (dbtype)
            {
                case "bigint": commonType = typeof(long); break;
                case "binary": commonType = typeof(byte[]); break;
                case "bit": commonType = typeof(bool); break;
                case "char": commonType = typeof(string); break;
                case "date": commonType = typeof(DateTime); break;
                case "datetime": commonType = typeof(DateTime); break;
                case "datetime2": commonType = typeof(DateTime); break;
                case "datetimeoffset": commonType = typeof(DateTimeOffset); break;
                case "decimal": commonType = typeof(decimal); break;
                case "float": commonType = typeof(double); break;
                case "image": commonType = typeof(byte[]); break;
                case "int": commonType = typeof(int); break;
                case "money": commonType = typeof(decimal); break;
                case "nchar": commonType = typeof(string); break;
                case "ntext": commonType = typeof(string); break;
                case "numeric": commonType = typeof(decimal); break;
                case "nvarchar": commonType = typeof(string); break;
                case "real": commonType = typeof(Single); break;
                case "smalldatetime": commonType = typeof(DateTime); break;
                case "smallint": commonType = typeof(short); break;
                case "smallmoney": commonType = typeof(decimal); break;
                case "sql_variant": commonType = typeof(object); break;
                case "sysname": commonType = typeof(object); break;
                case "text": commonType = typeof(string); break;
                case "time": commonType = typeof(TimeSpan); break;
                case "timestamp": commonType = typeof(byte[]); break;
                case "tinyint": commonType = typeof(byte); break;
                case "uniqueidentifier": commonType = typeof(Guid); break;
                case "varbinary": commonType = typeof(byte[]); break;
                case "varchar": commonType = typeof(string); break;
                case "xml": commonType = typeof(string); break;
                default: commonType = typeof(object); break;
            }
            return commonType;
        }
    }
    #endregion

#>

上面的代码就是查询数据库中的表和字段。

2、同样添加另一个T4模板文件，并修改后缀名Manager.ttinclude

<#@ assembly name="System.Data.Linq"
#><#@ assembly name="EnvDTE"
#><#@ assembly name="System.Xml"
#><#@ assembly name="System.Xml.Linq"
#><#@ import namespace="System.Collections.Generic"
#><#@ import namespace="System.IO"
#><#@ import namespace="System.Text"
#><#@ import namespace="Microsoft.VisualStudio.TextTemplating"
#><#+
// https://raw.github.com/damieng/DamienGKit
// http://damieng.com/blog/2009/11/06/multiple-outputs-from-t4-made-easy-revisited

// Manager class records the various blocks so it can split them up
class Manager {
    private class Block {
        public String Name;
        public int Start, Length;
        public bool IncludeInDefault;
    }

    private Block currentBlock;
    private readonly List<Block> files = new List<Block>();
    private readonly Block footer = new Block();
    private readonly Block header = new Block();
    private readonly ITextTemplatingEngineHost host;
    private readonly StringBuilder template;
    protected readonly List<String> generatedFileNames = new List<String>();

    public static Manager Create(ITextTemplatingEngineHost host, StringBuilder template) {
        return (host is IServiceProvider) ? new VSManager(host, template) : new Manager(host, template);
    }

    public void StartNewFile(String name) {
        if (name == null)
            throw new ArgumentNullException("name");
        CurrentBlock = new Block { Name = name };
    }

    public void StartFooter(bool includeInDefault = true) {
        CurrentBlock = footer;
        footer.IncludeInDefault = includeInDefault;
    }

    public void StartHeader(bool includeInDefault = true) {
        CurrentBlock = header;
        header.IncludeInDefault = includeInDefault;
    }

    public void EndBlock() {
        if (CurrentBlock == null)
            return;
        CurrentBlock.Length = template.Length - CurrentBlock.Start;
        if (CurrentBlock != header && CurrentBlock != footer)
            files.Add(CurrentBlock);
        currentBlock = null;
    }

    public virtual void Process(bool split, bool sync = true) {
        if (split) {
            EndBlock();
            String headerText = template.ToString(header.Start, header.Length);
            String footerText = template.ToString(footer.Start, footer.Length);
            String outputPath = Path.GetDirectoryName("host.TemplateFile");
            files.Reverse();
            if (!footer.IncludeInDefault)
                template.Remove(footer.Start, footer.Length);
            foreach(Block block in files) {
                String fileName = Path.Combine(outputPath, block.Name);
                String content = headerText + template.ToString(block.Start, block.Length) + footerText;
                generatedFileNames.Add(fileName);
                CreateFile(fileName, content);
                template.Remove(block.Start, block.Length);
            }
            if (!header.IncludeInDefault)
                template.Remove(header.Start, header.Length);
        }
    }

    protected virtual void CreateFile(String fileName, String content) {
        if (IsFileContentDifferent(fileName, content))
            File.WriteAllText(fileName, content);
    }

    public virtual String GetCustomToolNamespace(String fileName) {
        return null;
    }

    public virtual String DefaultProjectNamespace {
        get { return null; }
    }

    protected bool IsFileContentDifferent(String fileName, String newContent) {
        return !(File.Exists(fileName) && File.ReadAllText(fileName) == newContent);
    }

    private Manager(ITextTemplatingEngineHost host, StringBuilder template) {
        this.host = host;
        this.template = template;
    }

    private Block CurrentBlock {
        get { return currentBlock; }
        set {
            if (CurrentBlock != null)
                EndBlock();
            if (value != null)
                value.Start = template.Length;
            currentBlock = value;
        }
    }

    private class VSManager: Manager {
        private readonly EnvDTE.ProjectItem templateProjectItem;
        private readonly EnvDTE.DTE dte;
        private readonly Action<String> checkOutAction;
        private readonly Action<List<String>> projectSyncAction;

        public override String DefaultProjectNamespace {
            get {
                return templateProjectItem.ContainingProject.Properties.Item("DefaultNamespace").Value.ToString();
            }
        }

        public override String GetCustomToolNamespace(string fileName) {
            return dte.Solution.FindProjectItem(fileName).Properties.Item("CustomToolNamespace").Value.ToString();
        }

        public override void Process(bool split, bool sync) {
            if (templateProjectItem.ProjectItems == null)
                return;
            base.Process(split, sync);
            if (sync)
                projectSyncAction.EndInvoke(projectSyncAction.BeginInvoke(generatedFileNames, null, null));
        }

        protected override void CreateFile(String fileName, String content) {
            if (IsFileContentDifferent(fileName, content)) {
                CheckoutFileIfRequired(fileName);
                File.WriteAllText(fileName, content);
            }
        }

        internal VSManager(ITextTemplatingEngineHost host, StringBuilder template)
            : base(host, template) {
            var hostServiceProvider = (IServiceProvider)host;
            if (hostServiceProvider == null)
                throw new ArgumentNullException("Could not obtain IServiceProvider");
            dte = (EnvDTE.DTE) hostServiceProvider.GetService(typeof(EnvDTE.DTE));
            if (dte == null)
                throw new ArgumentNullException("Could not obtain DTE from host");
            templateProjectItem = dte.Solution.FindProjectItem(host.TemplateFile);
            checkOutAction = fileName => dte.SourceControl.CheckOutItem(fileName);
            projectSyncAction = keepFileNames => ProjectSync(templateProjectItem, keepFileNames);
        }

        private static void ProjectSync(EnvDTE.ProjectItem templateProjectItem, List<String> keepFileNames) {
            var keepFileNameSet = new HashSet<String>(keepFileNames);
            var projectFiles = new Dictionary<String, EnvDTE.ProjectItem>();
            var originalFilePrefix = Path.GetFileNameWithoutExtension(templateProjectItem.FileNames[]) + ".";
            foreach (EnvDTE.ProjectItem projectItem in templateProjectItem.ProjectItems)
                projectFiles.Add(projectItem.FileNames[], projectItem);

            // Remove unused items from the project
            foreach (var pair in projectFiles)
                if (!keepFileNames.Contains(pair.Key) && !(Path.GetFileNameWithoutExtension(pair.Key) + ".").StartsWith(originalFilePrefix))
                    pair.Value.Delete();

            // Add missing files to the project
            foreach(String fileName in keepFileNameSet)
                if (!projectFiles.ContainsKey(fileName))
                    templateProjectItem.ProjectItems.AddFromFile(fileName);
        }

        private void CheckoutFileIfRequired(String fileName) {
            var sc = dte.SourceControl;
            if (sc != null && sc.IsItemUnderSCC(fileName) && !sc.IsItemCheckedOut(fileName))
                checkOutAction.EndInvoke(checkOutAction.BeginInvoke(fileName, null, null));
        }
    }
} #>

上面的代码是用来生成多文件的。

3、新建T4模板文件PocoManager.tt，然后引入上面两个ttinclude文件。

<#@ template debug="false" hostspecific="true" language="C#" #>
<#@ assembly name="System.Data" #>
<#@ assembly name="System.Data.DataSetExtensions.dll" #>
<#@ assembly name="System.xml" #>
<#@ import namespace="System" #>
<#@ import namespace="System.Xml" #>
<#@ import namespace="System.Collections.Generic" #>
<#@ import namespace="System.Data" #>
<#@ import namespace="System.Data.SqlClient" #>
<#@ import namespace="System.IO" #>
<#@ assembly name="System.Core" #>
<#@ import namespace="System.Linq" #>
<#@include file="$(ProjectDir)Models\DbHelper.ttinclude"#>
<#@include file="$(ProjectDir)Models\Manager.ttinclude"#>
<# var manager = Manager.Create(Host, GenerationEnvironment); #>
<# manager.StartHeader(); #>
using System;
using System.Collections.Generic;
namespace My.Model
{
<# manager.EndBlock(); #>
<#
    foreach (DbTable db in DbHelper.GetDbTables(config.ConnectionString, config.DbDatabase))
    {
        string tb_name=db.TableName;
        manager.StartNewFile(tb_name+".cs");#>
    /// <summary>
    /// 实体-<#=tb_name#>
    /// </summary>
   public partial class <#=tb_name#>
    {
        <# foreach(DbColumn column in DbHelper.GetDbColumns(config.ConnectionString, config.DbDatabase, tb_name)){#>
/// <summary>
        /// <#=column.Remark#>
        /// </summary>
        public <#= column.CSharpType#><# if(column.CommonType.IsValueType && column.IsNullable){#>?<#}#> <#=column.ColumnName#> { get; set; }<#}#>
    }
<#//manager.EndBlock();
    }
    //conn.Close();
#>

<# manager.StartFooter(); #>
}
<# manager.EndBlock(); #>

<# manager.Process(true); #>
<#+
    public class config
    {
        public static readonly string ConnectionString="Data Source=(local);Integrated Security=true;Initial Catalog=CarSYS;";
        public static readonly string DbDatabase="CarSYS";
    }
#>

按Ctrl+S生成的代码如下：

using System;
using System.Collections.Generic;
namespace My.Model
{
    /// <summary>
    /// 实体-Brand
    /// </summary>
   public partial class Brand
    {
        /// <summary>
        /// 编号
        /// </summary>
        public int BrandId { get; set; }
        /// <summary>
        ///
        /// </summary>
        public string BrandName { get; set; }

    }
    /// <summary>
    /// 实体-Car
    /// </summary>
   public partial class Car
    {
        /// <summary>
        /// 编号
        /// </summary>
        public int CarId { get; set; }
        /// <summary>
        /// 车名称
        /// </summary>
        public string CarName { get; set; }
        /// <summary>
        /// 品牌编号
        /// </summary>
        public int? BrandId { get; set; }
        /// <summary>
        /// 实体图的文件名
        /// </summary>
        public string Picture { get; set; }
        /// <summary>
        /// 官方价
        /// </summary>
        public decimal OfficialPrice { get; set; }
        /// <summary>
        /// 点击率
        /// </summary>
        public int? Click { get; set; }

    }
    /// <summary>
    /// 实体-Product
    /// </summary>
   public partial class Product
    {
        /// <summary>
        ///
        /// </summary>
        public Guid Id { get; set; }
        /// <summary>
        ///
        /// </summary>
        public string NAME { get; set; }
        /// <summary>
        ///
        /// </summary>
        public decimal Price { get; set; }

    }

}

方式二

操作方式一种的步骤2，然后新建T4模板Manager.tt，引入Manager.ttinclude

<#@ template debug="false" hostspecific="true" language="C#" #>
<#@ assembly name="System.Data" #>
<#@ assembly name="System.xml" #>
<#@ import namespace="System.Collections.Generic" #>
<#@ import namespace="System.Data.SqlClient" #>
<#@ import namespace="System.Data" #>
<#@ assembly name="System.Core" #>
<#@ import namespace="System.Linq" #>
<#@include file="$(ProjectDir)Models\Manager.ttinclude"#>
<# var manager = Manager.Create(Host, GenerationEnvironment); #>
<# manager.StartHeader(); #>
using System;
using System.Collections.Generic;
namespace My.Model
{
<# manager.EndBlock(); #>

<#
    string connectionString= "server=localhost;database=CarSYS;uid=sa;pwd=1127;";
    SqlConnection conn = new SqlConnection(connectionString);
    conn.Open();

    string selectQuery ="SET FMTONLY ON; select * from @tableName; SET FMTONLY OFF;";
    SqlCommand command = new SqlCommand(selectQuery,conn);
    SqlDataAdapter ad = new SqlDataAdapter(command);
    System.Data.DataSet ds = new DataSet();
    System.Data.DataTable schema = conn.GetSchema("Tables");

    foreach(System.Data.DataRow row in schema.Rows)
    {
        ds.Tables.Clear();
        string tb_name =row["TABLE_NAME"].ToString().Replace(" ","_");
        string tb_type=row["TABLE_TYPE"].ToString();
        if(tb_type!="BASE TABLE")
        {
            continue;
        }
        command.CommandText = selectQuery.Replace("@tableName","["+row["TABLE_NAME"].ToString()+"]");
        ad.FillSchema(ds,SchemaType.Mapped,tb_name);
        manager.StartNewFile(tb_name+".cs");
#>
    /// <summary>
    /// 实体-<#=tb_name#>
    /// </summary>
    public partial class <#=tb_name#>
    {
        <#
        //PushIndent("        ");
        foreach (DataColumn dc in ds.Tables[].Columns)
        {
            string dataTypeName=dc.DataType.Name=="Byte[]"?"DateTime":dc.DataType.Name;
        #>
        /// <summary>
        /// <#=dc#>
        /// </summary>
       <#
        WriteLine("public " + dataTypeName + (dc.AllowDBNull && dataTypeName.ToLower() != "string" ? "? ": " ") + dc.ColumnName + " { get; set; }");
        }
        PopIndent();
        #>
    }
<#
        manager.EndBlock();
    }
    conn.Close();
#>

<# manager.StartFooter(); #>
}
<# manager.EndBlock(); #>

<# manager.Process(true); #>

按Ctrl+S生成的代码如下：

using System;
using System.Collections.Generic;
namespace My.Model
{   

    /// <summary>
    /// 实体-Brand
    /// </summary>
    public partial class Brand
    {
                /// <summary>
        /// BrandId
        /// </summary>
       public Int32 BrandId { get; set; }
        /// <summary>
        /// BrandName
        /// </summary>
       public String BrandName { get; set; }
    }
    /// <summary>
    /// 实体-Car
    /// </summary>
    public partial class Car
    {
                /// <summary>
        /// CarId
        /// </summary>
       public Int32 CarId { get; set; }
        /// <summary>
        /// CarName
        /// </summary>
       public String CarName { get; set; }
        /// <summary>
        /// BrandId
        /// </summary>
       public Int32? BrandId { get; set; }
        /// <summary>
        /// Picture
        /// </summary>
       public String Picture { get; set; }
        /// <summary>
        /// OfficialPrice
        /// </summary>
       public Decimal OfficialPrice { get; set; }
        /// <summary>
        /// Click
        /// </summary>
       public Int32? Click { get; set; }
    }
    /// <summary>
    /// 实体-Product
    /// </summary>
    public partial class Product
    {
                /// <summary>
        /// Id
        /// </summary>
       public Guid Id { get; set; }
        /// <summary>
        /// NAME
        /// </summary>
       public String NAME { get; set; }
        /// <summary>
        /// Price
        /// </summary>
       public Decimal Price { get; set; }
    } 

}

数据库CarSYS的脚本下载地址：

USE [master]
GO

/****** Object:  Database [CarSYS]    Script Date: 2/17/2017 5:33:04 PM ******/
CREATE DATABASE [CarSYS]
 CONTAINMENT = NONE
 ON  PRIMARY
( NAME = N'CarSYS', FILENAME = N'F:\DatabaseFile\CarSYS.mdf' , SIZE = 212992KB , MAXSIZE = UNLIMITED, FILEGROWTH = 1024KB )
 LOG ON
( NAME = N'CarSYS_log', FILENAME = N'F:\DatabaseFile\CarSYS_log.ldf' , SIZE = 321088KB , MAXSIZE = 2048GB , FILEGROWTH = 10%)
GO

ALTER DATABASE [CarSYS] SET COMPATIBILITY_LEVEL = 110
GO

IF (1 = FULLTEXTSERVICEPROPERTY('IsFullTextInstalled'))
begin
EXEC [CarSYS].[dbo].[sp_fulltext_database] @action = 'enable'
end
GO

ALTER DATABASE [CarSYS] SET ANSI_NULL_DEFAULT OFF
GO

ALTER DATABASE [CarSYS] SET ANSI_NULLS OFF
GO

ALTER DATABASE [CarSYS] SET ANSI_PADDING OFF
GO

ALTER DATABASE [CarSYS] SET ANSI_WARNINGS OFF
GO

ALTER DATABASE [CarSYS] SET ARITHABORT OFF
GO

ALTER DATABASE [CarSYS] SET AUTO_CLOSE OFF
GO

ALTER DATABASE [CarSYS] SET AUTO_CREATE_STATISTICS ON
GO

ALTER DATABASE [CarSYS] SET AUTO_SHRINK OFF
GO

ALTER DATABASE [CarSYS] SET AUTO_UPDATE_STATISTICS ON
GO

ALTER DATABASE [CarSYS] SET CURSOR_CLOSE_ON_COMMIT OFF
GO

ALTER DATABASE [CarSYS] SET CURSOR_DEFAULT  GLOBAL
GO

ALTER DATABASE [CarSYS] SET CONCAT_NULL_YIELDS_NULL OFF
GO

ALTER DATABASE [CarSYS] SET NUMERIC_ROUNDABORT OFF
GO

ALTER DATABASE [CarSYS] SET QUOTED_IDENTIFIER OFF
GO

ALTER DATABASE [CarSYS] SET RECURSIVE_TRIGGERS OFF
GO

ALTER DATABASE [CarSYS] SET  DISABLE_BROKER
GO

ALTER DATABASE [CarSYS] SET AUTO_UPDATE_STATISTICS_ASYNC OFF
GO

ALTER DATABASE [CarSYS] SET DATE_CORRELATION_OPTIMIZATION OFF
GO

ALTER DATABASE [CarSYS] SET TRUSTWORTHY OFF
GO

ALTER DATABASE [CarSYS] SET ALLOW_SNAPSHOT_ISOLATION OFF
GO

ALTER DATABASE [CarSYS] SET PARAMETERIZATION SIMPLE
GO

ALTER DATABASE [CarSYS] SET READ_COMMITTED_SNAPSHOT OFF
GO

ALTER DATABASE [CarSYS] SET HONOR_BROKER_PRIORITY OFF
GO

ALTER DATABASE [CarSYS] SET RECOVERY FULL
GO

ALTER DATABASE [CarSYS] SET  MULTI_USER
GO

ALTER DATABASE [CarSYS] SET PAGE_VERIFY CHECKSUM
GO

ALTER DATABASE [CarSYS] SET DB_CHAINING OFF
GO

ALTER DATABASE [CarSYS] SET FILESTREAM( NON_TRANSACTED_ACCESS = OFF )
GO

ALTER DATABASE [CarSYS] SET TARGET_RECOVERY_TIME = 0 SECONDS
GO

ALTER DATABASE [CarSYS] SET  READ_WRITE
GO

扩展：我们还可以在搭建项目框架的时候，通过反射等技术来自己编写T4模板。

当然，我们还可以通过Entity Framework Power Tools这个开发神器来生成我们的EF Code代码。