实体类生成器

在开发基于三层架构的项目初期，都会按照数据库的表结构定义一堆的实体类，但是一个表里有那么多的字段，一个库又有那么多个表，建这些实体类的工作量不少，作为一个懒人，肯定想些法子解决这么麻烦的问题。写一个实体生成器。

　　为了生成器能兼容各仲类型的数据库，我把生成器的架构定义成如下形式

　　还是说明一下吧！在数据库的上一层定义了各种数据的Controler,负责建立各种数据的连接等等，在DAL的每一个类都实现IDAL接口， 每一种数据库的DAL类都定义了各自查询SQL，在BLL处通过读取配置，获知当前需要对哪个类型的数据库操作，再通过反射机制动态生成相应的DAL实 例。这样如果再有新的数据库类型，只要添加新的Controler类和新的DAL类，在配置中改一下就行了。

看一下程序的界面

项目的结构

　　Entitiy目录下的是本项目中需要的一些实体类，包括储存表信息的TableENT，列信息的ColumnENT,实体类文件信息的 CSFileENT。此生成器生成的类文件并不是通过模板文件来构造文件内容的，文件信息是通过配置文件来配置的，用 EntityFileConfig.xml来配置。

 　　生成实体类的时候要知道数据库里有什么表，表里头有什么字段，相关的SQL语句我只有SQL Server的，其他的数据库还没搞(或者有需要的时候才去搞，呵呵),所以这里暂时只能生成SQL Server的。

下面则各个类的代码，DBC里面的就不展示了，

首先是IDAL接口的，实现IDAL接口的类要实现4个方法，GetTableNames获取数据库表的名称，GetTableInfo根据表的名称获取表的字段信息，ConvertType把数据库的数据类型转换成.NET Framework的类型。

 1     public interface IDAL
 2     {
 3         List<TableENT> GetTabelNames( );
 4 
 5         List<ColumnENT> GetTabelInfo(string tableName);
 6 
 7         string ConvertType(string DbTypeName);
 8 
 9         bool TestConnect();
10     }

到MSSQLDAL

 1     public class MSSQLDAL:IDAL
 2     {
 3         public List<TableENT> GetTabelNames( )
 4         {
 5             List<TableENT> list = new List<TableENT>();
 6             MSSQLControler db = new MSSQLControler();
 7             string cmdText = "SELECT name FROM sysobjects WHERE type='U' ";
 8             DataTable table = db.GetDataTable(cmdText, null);
 9 
10             TableENT ent = null;
11             foreach (DataRow  row in table.Rows)
12             {
13                 ent = new TableENT();
14                 ent.TableName = row["name"]==DBNull.Value?string.Empty:row["name"].ToString();
15                 ent.State = StateEnum.Ready;
16                 list.Add(ent);
17             }
18 
19             return list;
20         }
21 
22         public List<ColumnENT> GetTabelInfo(string tableName)
23         {
24             List<ColumnENT> list = new List<ColumnENT>();
25 
26             MSSQLControler db = new MSSQLControler();
27             string cmdText = "sp_columns @TabelName ";
28             SqlParameter[] paraArr = new SqlParameter[] { new SqlParameter("@TabelName",tableName) };
29             DataTable table = db.GetDataTable(cmdText, paraArr);
30 
31             ColumnENT ent = null;
32             foreach (DataRow row in table.Rows)
33             {
34                 ent = new ColumnENT();
35                 ent.ColumnName = row["COLUMN_NAME"] == DBNull.Value ? string.Empty : row["COLUMN_NAME"].ToString();
36                 ent.DBTypeName = row["TYPE_NAME"] == DBNull.Value ? string.Empty : row["TYPE_NAME"].ToString();
37                 list.Add(ent);
38             }
39             return list;
40         }
41 
42         //分割类型名 
43         public string ConvertType(string DbTypeName)
44         {
45             switch (DbTypeName)
46             {
47                 case "bigint": return "Int64";
48                 case "datetimeoffset": return "DateTimeOffset";
49                 case "float": return "Double";
50                 case "int": return "Int32";
51                 case "real": return "Single";
52                 case "smallint": return "Int16";
53                 case "time": return "TimeSpan";
54                 case "uniqueidentifier": return "Guid";
55                 case "xml": return "Xml";
56                 case "bit": return "Boolean";
57                 case "tinyint": return "Byte";
58             }
59             if (DbTypeName == "char" ||
60                 DbTypeName == "nchar" ||
61                 DbTypeName == "ntext" ||
62                 DbTypeName == "nvarchar" ||
63                 DbTypeName == "text" ||
64                 DbTypeName == "varchar") return "String";
65 
66             if (DbTypeName == "FILESTREAM" ||
67                 DbTypeName == "binary" ||
68                 DbTypeName == "timestamp" ||
69                 DbTypeName == "image" ||
70                 DbTypeName == "rowversion" ||
71                 DbTypeName == "varbinary") return "Byte[]";
72 
73             if (DbTypeName == "datetime" ||
74                 DbTypeName == "date" ||
75                 DbTypeName == "datetime2" ||
76                 DbTypeName == "smalldatetime") return "DateTime";
77 
78 
79             if (DbTypeName == "decimal" ||
80                 DbTypeName == "money" ||
81                 DbTypeName == "numeric" ||
82                 DbTypeName == "smallmoney") return "Decimal";
83 
84             return "object";
85         }
86 
87         public bool TestConnect()
88         {
89             MSSQLControler db = new MSSQLControler();
90             return db.TestConnect();
91         }
92     }

到DbBLL,DbBLL是直接给窗体的事件方法调用的，

 1    public class DbBLL
 2     {
 3         private static string typeName = ConfigurationManager.AppSettings["TypeName"];
 4 
 5         private static string dllPath = ConfigurationManager.AppSettings["dllPath"];
 6 
 7         public List<TableENT> GetTabelNames( )
 8         {
 9             List<TableENT> list = new List<TableENT>();
10             IDAL dal = CreateDAL();
11             if (dal != null) list = dal.GetTabelNames();
12             return list;
13         }
14 
15         public bool CreateEntity(string TableName,string outPath)
16         {
17             IDAL dal = CreateDAL();
18             FileCommon fileBLL = new FileCommon();
19             if (dal == null) return false;
20             List<ColumnENT> colLlist = dal.GetTabelInfo(TableName);
21 
22             CSFileENT file = fileBLL.LoadModelFile();
23             foreach (ColumnENT item in colLlist)
24             {
25                 string colTemp = item.DBTypeName.Split().FirstOrDefault();
26                 item.EntTypeName = dal.ConvertType(colTemp);
27             }
28             file.ClassName = TableName;
29             string content = fileBLL.CreateFileContent(file, colLlist);
30 
31             bool result = false;
32             outPath = outPath.Trim('\\')+"\\" + TableName + "_ENT.cs";
33             result = fileBLL.OutputFile(content,outPath);
34             return result;
35         }
36 
37         public bool TestConnect()
38         {
39             bool result=false;
40             IDAL dal = CreateDAL();
41             if (dal != null) result = dal.TestConnect();
42             return result;
43         }
44 
45         private IDAL CreateDAL()
46         {
47             if (string.IsNullOrEmpty(typeName))
48                 throw new Exception("配置文件里的TypeName不存在或为空");
49             Assembly assembly;
50             if(string.IsNullOrEmpty(dllPath))assembly=Assembly.GetExecutingAssembly();
51             else assembly= Assembly.LoadFile("");
52             Type dalType = assembly.GetType(typeName);
53             IDAL typeIns =assembly.CreateInstance(typeName) as IDAL;
54             return typeIns;
55         }
56     }

FileCommon是生成代码的以及生成实体类文件的类

 1     public class FileCommon
 2     {
 3         public CSFileENT LoadModelFile( )
 4         {
 5             CSFileENT ent = new CSFileENT();
 6             XmlDocument config = new XmlDocument();
 7             config.Load("EntityFileConfig.xml");
 8             XmlNodeList nodeList = config.ChildNodes[1].ChildNodes;
 9             foreach (XmlNode node in nodeList)
10             {
11                 switch (node.Name)
12                 {
13                     case "using":
14                         XmlNodeList usingList = node.ChildNodes;
15                         foreach (XmlNode child in usingList)
16                         {
17                             ent.UsingText += "using " + child.Attributes["value"].Value + ";\r\n";
18                         }
19                         break;
20                     case "namespace":
21                         ent.NameSpaceText = node.Attributes["value"].Value;
22                         break;
23                     case "expand":
24                         XmlNodeList expandList = node.ChildNodes;
25                         foreach (XmlNode child in expandList)
26                         {
27                             ent.Expand += child.Attributes["value"].Value + ",";
28                         }
29                         ent.Expand=ent.Expand.Trim(',');
30                         break;
31                     case "fieldAttribute":
32                         ent.FieldAttribute = node.Attributes["value"].Value;
33                         break;
34                     case "classAttribute":
35                         ent.ClassAttribute = node.Attributes["value"].Value;
36                         break;
37                 }
38             }
39             return ent;
40         }
41 
42         public string CreateFileContent(CSFileENT file, List<ColumnENT> colList)
43         {
44             string result = string.Empty;
45 
46             result += file.UsingText+"{0}";
47             if (!string.IsNullOrEmpty(file.NameSpaceText))
48                 result = string.Format(result, "\r\nnamespace " + file.NameSpaceText + "\r\n{\r\n\t $$ \r\n}").Replace("$$","{0}");
49             result= result.Replace("{0}",file.ClassAttribute + "\r\n\tpublic class " + file.ClassName+"{0}");
50             if (!string.IsNullOrEmpty(file.Expand))
51                 result =result.Replace("{0}", ":"+file.Expand+"{0}");
52             result =result.Replace("{0}", "\r\n\t{\r\n\t\t{0}\r\n\t}");
53 
54             foreach (ColumnENT col in colList)
55             {
56                 string fildText = string.Empty;
57                 if (!string.IsNullOrEmpty(file.FieldAttribute))
58                     fildText += file.FieldAttribute + "\r\n\t\t";
59                 fildText += "public " + col.EntTypeName + " " + col.ColumnName;
60                 result = result.Replace("{0}", fildText + " {get;set;}\r\n\r\n\t\t{0}");
61             }
62 
63             result = result.Replace("{0}","");
64 
65             return result;
66         }
67 
68         public bool OutputFile(string context,string outputPath)
69         {
70             bool result = false;
71 
72             try
73             {
74                 File.WriteAllText(outputPath, context);
75                 result=true;
76             }
77             catch { result = false; }
78             return result;
79         }
80     }

界面的代码就不列举了，接下来到介绍程序的配置

生成实体类的配置

 1 <entityConfig>
 2   <using>
 3     <add value="System" />
 4   </using>
 5   <namespace value="ENT"/>
 6   <expand>
 7     <add value=""/>
 8   </expand>
 9   <fieldAttribute value=""/>
10   <classAttribute value=""/>
11 </entityConfig>

using填的是要引用到的命名空间，namespace是生成类的命名空间的名字，expand是生成类要继承的类和实现的接口的列 表，fieldAttribute是字段的Attribute值，classAttribute是类的Attribute，这两个Attribute在 WCF方面有用的。

程序配置

1 <configuration>
2   <appSettings>
3     <add key="connectionstring" value="Data Source=localhost\SQLEXPRESS;Initial Catalog=HOMEMAKINGSYSTEM;Integrated Security=true;"/>
4     <add key="TypeName" value="EntityCreator.DAL.MSSQLDAL"/><!--SQL Server:EntityCreator.DAL.MSSQLDAL -->
5     <add key="dllPath" value=""/>
6   </appSettings>
7 
8 </configuration>

connectionstring不用说了；TypeName是当前要调用那个DAL类的完全限定名；若添加了新类型的数据库，可以把新的DAL和Controler类编译成dll,然后把dll的路径放到dllPath里，程序则会生成相应的实例了。

 

经各位过路大侠们指教才发现原来有codesmith这么一个好东西，鄙人真是孤陋寡闻了。

补充两篇博文，是写这个生成器前的准备知识 《各种数据库查询表及表信息的SQL》和《各种数据库与.NET Framework类型对照》

posted @ 2013-02-13 17:07  Tony.J  阅读(815)  评论(0)  编辑  收藏  举报