c# 使用T4模板生成实体类（sqlserver）

新建类库，右键添加 "文本模板"

添加完成之后生成如下后缀为 tt的文件：

 

 双击文件：texttemplate_test.tt 文件打开，替换代码如下

 1 <#@ template debug="false" hostspecific="true" language="c#" #>
 2 <#@ assembly name="system.core" #>
 3 <#@ assembly name="system.data" #>
 4 <#@ assembly name="system.xml" #>
 5 <#@ import namespace="system.linq" #>
 6 <#@ import namespace="system.text" #>
 7 <#@ import namespace="system.collections.generic" #>
 8 <#@ import namespace="system.data.sqlclient" #>
 9 <#@ import namespace="system.data" #>
10 <#@ include file="modelauto.ttinclude"#>
11 <#@ output extension=".cs" #>
12 
13 <# var manager = new manager(host, generationenvironment, true) { outputpath = path.getdirectoryname(host.templatefile)}; #>
14 <# 
15     //数据库连接
16     string connectionstring ="data source=127.0.0.1;initial catalog=testdb;user id=sa;password=123456;"; 
17     sqlconnection conn = new sqlconnection(connectionstring); 
18     conn.open(); 
19     //查询表
20     system.data.datatable schema = conn.getschema("tables"); 
21     string selectquery = "select * from @tablename";   //查询表语句
22     sqlcommand command = new sqlcommand(selectquery,conn); 
23     sqldataadapter ad = new sqldataadapter(command); 
24     system.data.dataset ds = new dataset();
25     //查询字段
26     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'"; 
27     sqlcommand command2 = new sqlcommand(propquery,conn); 
28     sqldataadapter ad2 = new sqldataadapter(command2); 
29     system.data.dataset ds2 = new dataset();
30  #>
31 
32 <# foreach(system.data.datarow row in schema.rows) { #>
33 <# manager.startblock(row["table_name"].tostring()+".cs"); #>
34 using system;
35 
36 namespace entity.model
37 {
38     /// <summary>
39     /// 实体类：<#= row["table_name"].tostring() #> 
40     /// </summary>
41     [serializable]
42     public class <#= row["table_name"].tostring() #>
43     {
44         <# 
45         ds.tables.clear();
46         command.commandtext = selectquery.replace("@tablename","["+row["table_name"].tostring()+"]"); 
47         ad.fillschema(ds, schematype.mapped, row["table_name"].tostring());
48         foreach (datacolumn dc in ds.tables[0].columns)
49         { 
50         #>
51             <# 
52             ds2.tables.clear();
53             command2.commandtext = propquery.replace("@tablename",row["table_name"].tostring()); 
54             command2.commandtext = command2.commandtext.replace("@columnname",dc.columnname); 
55             ad2.fill(ds2);
56             #>
57 
58         ///<summary>
59         ///<#= manager.transfromsqltype(dc.datatype.name) #>:<#=ds2.tables[0].rows[0].itemarray[2]#>
60         ///</summary>
61         public <#= manager.transfromsqltype(dc.datatype.name) #> <#= dc.columnname #> { get; set; }  
62         <#}#>    
63     }
64 }
65 
66 <# manager.endblock(); #>
67 
68 <#}#>
69 
70 <#manager.process(true);#>

需要更换几个配置的地方：

1，设置数据库连接，找到该段代码：string connectionstring ="data source=127.0.0.1;initial catalog=testdb;user id=sa;password=123456;";  替换你要连接的数据库即可；

2，设置命名空间，找到代码：namespace entity.model {....} ，将该处的命名空间替换你要的即可；

3，相同目录下添加代码自动生成逻辑文件，文件名字为：modelauto.ttinclude

文件内容如下，

  1 <#@ assembly name="system.core"#>
  2 <#@ assembly name="envdte"#>
  3 <#@ import namespace="system.collections.generic"#>
  4 <#@ import namespace="system.io"#>
  5 <#@ import namespace="system.text"#>
  6 <#@ import namespace="microsoft.visualstudio.texttemplating"#>
  7 
  8 <#+
  9 
 10 class manager
 11 {
 12     public struct block {
 13         public string name;
 14         public int start, length;
 15     }
 16 
 17     public list<block> blocks = new list<block>();
 18     public block currentblock;
 19     public block footerblock = new block();
 20     public block headerblock = new block();
 21     public itexttemplatingenginehost host;
 22     public managementstrategy strategy;
 23     public stringbuilder template;
 24     public string outputpath { get; set; }
 25 
 26     public manager(itexttemplatingenginehost host, stringbuilder template, bool commonheader) {
 27         this.host = host;
 28         this.template = template;
 29         outputpath = string.empty;
 30         strategy = managementstrategy.create(host);
 31     }
 32 
 33     public void startblock(string name) {
 34         currentblock = new block { name = name, start = template.length };
 35     }
 36 
 37     public void startfooter() {
 38         footerblock.start = template.length;
 39     }
 40 
 41     public void endfooter() {
 42         footerblock.length = template.length - footerblock.start;
 43     }
 44 
 45     public void startheader() {
 46         headerblock.start = template.length;
 47     }
 48 
 49     public void endheader() {
 50         headerblock.length = template.length - headerblock.start;
 51     }    
 52 
 53     public void endblock() {
 54         currentblock.length = template.length - currentblock.start;
 55         blocks.add(currentblock);
 56     }
 57 
 58     public void process(bool split) {
 59         string header = template.tostring(headerblock.start, headerblock.length);
 60         string footer = template.tostring(footerblock.start, footerblock.length);
 61         blocks.reverse();
 62         foreach(block block in blocks) {
 63             string filename = path.combine(outputpath, block.name);
 64             if (split) {
 65                 string content = header + template.tostring(block.start, block.length) + footer;
 66                 strategy.createfile(filename, content);
 67                 template.remove(block.start, block.length);
 68             } else {
 69                 strategy.deletefile(filename);
 70             }
 71         }
 72     }
 73 
 74         /// <summary>
 75         /// sql[不完善,需要的自己改造]
 76         /// 更换字段类型
 77         /// </summary>
 78         /// <param name="type"></param>
 79         /// <returns></returns>
 80         public string transfromsqltype(string type)
 81         {
 82             if (string.isnullorempty(type))
 83             {
 84                 return string.empty;
 85             }
 86             if (string.equals(type, "boolean", stringcomparison.ordinalignorecase))
 87             {
 88                 return "bool";
 89             }
 90             else if (string.equals(type, "int32", stringcomparison.ordinalignorecase))
 91             {
 92                 return "int";
 93             }
 94             else if (string.equals(type, "int64", stringcomparison.ordinalignorecase))
 95             {
 96                 return "long";
 97             }
 98             else if (string.equals(type, "string", stringcomparison.ordinalignorecase))
 99             {
100                 return "string";
101             }
102             else if(string.equals(type, "byte", stringcomparison.ordinalignorecase))
103             {
104                 return "byte";
105             }
106             else if (string.equals(type, "decimal", stringcomparison.ordinalignorecase))
107             {
108                 return "decimal";
109             }
110             else if (string.equals(type, "datetime", stringcomparison.ordinalignorecase))
111             {
112                 return "datetime";
113             }
114             return "string";
115         }
116 
117 }
118 
119 class managementstrategy
120 {
121     internal static managementstrategy create(itexttemplatingenginehost host) {
122         return (host is iserviceprovider) ? new vsmanagementstrategy(host) : new managementstrategy(host);
123     }
124 
125     internal managementstrategy(itexttemplatingenginehost host) { }
126 
127     internal virtual void createfile(string filename, string content) {
128         file.writealltext(filename, content);
129     }
130 
131     internal virtual void deletefile(string filename) {
132         if (file.exists(filename))
133             file.delete(filename);
134     }
135 }
136 
137 class vsmanagementstrategy : managementstrategy
138 {
139     private envdte.projectitem templateprojectitem;
140 
141     internal vsmanagementstrategy(itexttemplatingenginehost host) : base(host) {
142         iserviceprovider hostserviceprovider = (iserviceprovider)host;
143         if (hostserviceprovider == null)
144             throw new argumentnullexception("could not obtain hostserviceprovider");
145 
146         envdte.dte dte = (envdte.dte)hostserviceprovider.getservice(typeof(envdte.dte));
147         if (dte == null)
148             throw new argumentnullexception("could not obtain dte from host");
149 
150         templateprojectitem = dte.solution.findprojectitem(host.templatefile);
151     }
152 
153     internal override void createfile(string filename, string content) {
154         base.createfile(filename, content);
155         ((eventhandler)delegate { templateprojectitem.projectitems.addfromfile(filename); }).begininvoke(null, null, null, null);
156     }
157 
158     internal override void deletefile(string filename) {
159         ((eventhandler)delegate { findanddeletefile(filename); }).begininvoke(null, null, null, null);
160     }
161 
162     private void findanddeletefile(string filename) {
163         foreach(envdte.projectitem projectitem in templateprojectitem.projectitems) {
164             if (projectitem.get_filenames(0) == filename) {
165                 projectitem.delete();
166                 return;
167             }
168         }
169     }
170 }#>

接下来就是见证奇迹的时刻，选中 texttemplate_test.tt 文件 按 ctrl+c即可(每次更新实体类时,需要先修改一下模板文件,随便修改什么地方，按个空格也可以)，生成模板代码如下：