T4模版自动生成MSSQL实体类

在Model层建立ModelAuto.ttinclude文件

<#@ assembly name="System.Core"#>
<#@ assembly name="EnvDTE"#>
<#@ import namespace="System.Collections.Generic"#>
<#@ import namespace="System.IO"#>
<#@ import namespace="System.Text"#>
<#@ import namespace="Microsoft.VisualStudio.TextTemplating"#>

<#+

class Manager
{
    public struct Block {
        public String Name;
        public int Start, Length;
    }

    public List<Block> blocks = new List<Block>();
    public Block currentBlock;
    public Block footerBlock = new Block();
    public Block headerBlock = new Block();
    public ITextTemplatingEngineHost host;
    public ManagementStrategy strategy;
    public StringBuilder template;
    public String OutputPath { get; set; }

    public Manager(ITextTemplatingEngineHost host, StringBuilder template, bool commonHeader) {
        this.host = host;
        this.template = template;
        OutputPath = String.Empty;
        strategy = ManagementStrategy.Create(host);
    }

    public void StartBlock(String name) {
        currentBlock = new Block { Name = name, Start = template.Length };
    }

    public void StartFooter() {
        footerBlock.Start = template.Length;
    }

    public void EndFooter() {
        footerBlock.Length = template.Length - footerBlock.Start;
    }

    public void StartHeader() {
        headerBlock.Start = template.Length;
    }

    public void EndHeader() {
        headerBlock.Length = template.Length - headerBlock.Start;
    }    

    public void EndBlock() {
        currentBlock.Length = template.Length - currentBlock.Start;
        blocks.Add(currentBlock);
    }

    public void Process(bool split) {
        String header = template.ToString(headerBlock.Start, headerBlock.Length);
        String footer = template.ToString(footerBlock.Start, footerBlock.Length);
        blocks.Reverse();
        foreach(Block block in blocks) {
            String fileName = Path.Combine(OutputPath, block.Name);
            if (split) {
                String content = header + template.ToString(block.Start, block.Length) + footer;
                strategy.CreateFile(fileName, content);
                template.Remove(block.Start, block.Length);
            } else {
                strategy.DeleteFile(fileName);
            }
        }
    }
}

class ManagementStrategy
{
    internal static ManagementStrategy Create(ITextTemplatingEngineHost host) {
        return (host is IServiceProvider) ? new VSManagementStrategy(host) : new ManagementStrategy(host);
    }

    internal ManagementStrategy(ITextTemplatingEngineHost host) { }

    internal virtual void CreateFile(String fileName, String content) {
        File.WriteAllText(fileName, content);
    }

    internal virtual void DeleteFile(String fileName) {
        if (File.Exists(fileName))
            File.Delete(fileName);
    }
}

class VSManagementStrategy : ManagementStrategy
{
    private EnvDTE.ProjectItem templateProjectItem;

    internal VSManagementStrategy(ITextTemplatingEngineHost host) : base(host) {
        IServiceProvider hostServiceProvider = (IServiceProvider)host;
        if (hostServiceProvider == null)
            throw new ArgumentNullException("Could not obtain hostServiceProvider");

        EnvDTE.DTE 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);
    }

    internal override void CreateFile(String fileName, String content) {
        base.CreateFile(fileName, content);
        ((EventHandler)delegate { templateProjectItem.ProjectItems.AddFromFile(fileName); }).BeginInvoke(null, null, null, null);
    }

    internal override void DeleteFile(String fileName) {
        ((EventHandler)delegate { FindAndDeleteFile(fileName); }).BeginInvoke(null, null, null, null);
    }

    private void FindAndDeleteFile(String fileName) {
        foreach(EnvDTE.ProjectItem projectItem in templateProjectItem.ProjectItems) {
            if (projectItem.get_FileNames() == fileName) {
                projectItem.Delete();
                return;
            }
        }
    }
}#>

在编写T4模版

<#@ template language="C#" debug="True" hostspecific="True" #>
<#@ output extension=".cs" #>
<#@ assembly name="System.Data" #>
<#@ assembly name="System.xml" #>
<#@ import namespace="System.Collections.Generic" #>
<#@ import namespace="System.Data.SqlClient" #>
<#@ import namespace="System.Data" #>
<#@ include file="ModelAuto.ttinclude"#>
<# var manager = new Manager(Host, GenerationEnvironment, true) { OutputPath = Path.GetDirectoryName(Host.TemplateFile)}; #>
<#
    string connectionString = "Data Source=.;Initial Catalog=MiniProfilerDemo;User ID=sa;Password=tfc063318;";
    SqlConnection conn = new SqlConnection(connectionString);
    conn.Open();
    System.Data.DataTable schema = conn.GetSchema("TABLES");
    string selectQuery = "select * from @tableName";
    SqlCommand command = new SqlCommand(selectQuery,conn);
    SqlDataAdapter ad = new SqlDataAdapter(command);
    System.Data.DataSet ds = new DataSet();

    string propQuery = "SELECT 表名=sobj.name,字段名=scol.name,字段说明=sprop.[value] FROM syscolumns as scol inner join sys.sysobjects as sobj on scol.id=sobj.id and sobj.xtype='U' and sobj.name<>'dtproperties' left join sys.extended_properties as sprop on scol.id=sprop.major_id and scol.colid=sprop.minor_id where sobj.name='@tableName' and scol.name='@columnName'";
    SqlCommand command2 = new SqlCommand(propQuery,conn);
    SqlDataAdapter ad2 = new SqlDataAdapter(command2);
    System.Data.DataSet ds2 = new DataSet();
 #>

<#
    foreach(System.Data.DataRow row in schema.Rows)
    {  #>   

     <#
        manager.StartBlock(row["TABLE_NAME"]+".cs");
     #>
    //----------<#=row["TABLE_NAME"].ToString()#>开始----------

    using System;
    namespace MyProject.Entities
    {
        /// <summary>
        /// 数据表实体类：<#= row["TABLE_NAME"].ToString() #>
        /// </summary>
        [Serializable()]
        public class <#= row["TABLE_NAME"].ToString() #>
        {
            <#
            ds.Tables.Clear();
            command.CommandText = selectQuery.Replace("@tableName",row["TABLE_NAME"].ToString());
            ad.FillSchema(ds, SchemaType.Mapped, row["TABLE_NAME"].ToString());
            foreach (DataColumn dc in ds.Tables[].Columns)
            {
            #>
            <#
             ds2.Tables.Clear();
             command2.CommandText = propQuery.Replace("@tableName",row["TABLE_NAME"].ToString());
             command2.CommandText = command2.CommandText.Replace("@columnName",dc.ColumnName);
             ad2.Fill(ds2);
            #>
            /// <summary>
            /// <#= dc.DataType.Name #>:<#=ds2.Tables[0].Rows[0].ItemArray[2]#>
            /// </summary>
            public <#= dc.DataType.Name #> <#= dc.ColumnName #> {get;set;}
            <# }  #>
        }
     }

    //----------<#=row["TABLE_NAME"].ToString()#>结束----------

    <# manager.EndBlock(); #>

<#
    } #> 

<#
    manager.Process(true);
#>

注意:T4模版中需要修改数据库连接字符串和命名空间

保存,就可以生成MSSQL数据库的实体类啦!!