Dbml文件提取建表TSqlCodeSmith

     在昨天一个大学师弟，他问我能不能将LinqToSql文件转化为创建表的TSql语句，他是刚开始学习.NET，所以在网上下些示例看，但苦于没有数据库。所以就有了这一篇博客，作为我的Code生成技术的CodeSimth的最后一篇示例。在下一步Code 生成技术将转到Microsoft的T4模板，Code生成技术目前完成的有CodeDom,CodeSmith模板，高手请不要拍砖，请直接跳过。

     在Linq2Sql的Dbml文件其实就是一个Xml文件，记录着数据库与生成Linq2SqlCode的数据信息，所以转化为TSql没有什么说的。我们需要提取其中的数据库信息，在转化为我们的Tsql，在这里建立了DBTable、DBColumn、DBAssociation三个实体类：

  1 using System; 
  2 using System.Collections.Generic; 
  3 using System.Linq; 
  4 using System.Text; 
  5 
  6 namespace DbmlToTable 
  7 { 
  8     public class DBTable 
  9     { 
 10 
 11         public DBTable() 
 12         { 
 13             Columns = new List<DBColumn>(); 
 14             this.Associations = new List<DBAssociation>(); 
 15         } 
 16 
 17         public string TableName 
 18         { 
 19             get; 
 20             set; 
 21         } 
 22 
 23         public List<DBColumn> Columns 
 24         { 
 25             get; 
 26             set; 
 27         } 
 28 
 29         public List<DBAssociation> Associations 
 30         { 
 31             get; 
 32             set; 
 33         } 
 34 
 35     } 
 36 
 37     public class DBColumn 
 38     { 
 39         public string Name 
 40         { 
 41             get; 
 42             set; 
 43         } 
 44 
 45         public string DBType 
 46         { 
 47             get; 
 48             set; 
 49         } 
 50 
 51         public bool IsPrimaryKey 
 52         { 
 53             get; 
 54             set; 
 55         } 
 56 
 57         public bool IsDbGenerated 
 58         { 
 59             get; 
 60             set; 
 61         } 
 62 
 63         public bool CanBeNull 
 64         { 
 65             get; 
 66             set; 
 67         } 
 68     } 
 69 
 70     public class DBAssociation 
 71     { 
 72         public string Name 
 73         { 
 74             get; 
 75             set; 
 76         } 
 77 
 78         public string ThisKey 
 79         { 
 80             get; 
 81             set; 
 82         } 
 83 
 84         public string OtherKey 
 85         { 
 86             get; 
 87             set; 
 88         } 
 89 
 90         public bool IsForeignKey 
 91         { 
 92             get; 
 93             set; 
 94         } 
 95     } 
 96 
 97     public class DBTableHlper 
 98     { 
 99         public static DBTable GetAssociationTable(List<DBTable> collection,string assName) 
100         { 
101 
102             return collection.Find(t => t.Associations.Find(a => !a.IsForeignKey && a.Name == assName) != null); 
103         } 
104     } 
105 }
106 
107 

    其中DBTableHlper是由于我的Codesimth是2.0版本的，不能用lamdam表达式，所以我将它编译在程序集里面。

   建立了一个 将我们的dbml文件xml Document转化为实体类辅助类：

 1 using System; 
 2 using System.Collections.Generic; 
 3 using System.Linq; 
 4 using System.Text; 
 5 using System.Xml; 
 6 using System.Xml.Linq; 
 7 
 8 namespace DbmlToTable 
 9 { 
10 
11     public interface IDbTableCollectionHelper 
12     { 
13         List<DBTable> Transport(XElement element); 
14     } 
15 
16     public class DbTableCollectionHelper : IDbTableCollectionHelper 
17     { 
18         #region IDbTableCollectionHelper 成员 
19 
20         public List<DBTable> Transport(XElement element) 
21         { 
22             List<DBTable> collection = new List<DBTable>(); 
23             var tables = element.Elements(XName.Get("Table", "http://schemas.microsoft.com/linqtosql/dbml/2007%22)); 
24             foreach (var tab in tables) 
25             { 
26                 DBTable t = new DBTable() { TableName = tab.Attribute("Name").Value }; 
27                 var cols = tab.Element(XName.Get("Type", "http://schemas.microsoft.com/linqtosql/dbml/2007%22)).Elements(XName.Get(%22Column%22, "http://schemas.microsoft.com/linqtosql/dbml/2007%22)); 
28                 foreach (var col in cols) 
29                 { 
30                     DBColumn c = new DBColumn() 
31                     { 
32                         CanBeNull = col.Attribute("CanBeNull") != null ? col.Attribute("CanBeNull").Value.ToLower() == "true" : false, 
33                         DBType = col.Attribute("DbType") != null ? col.Attribute("DbType").Value : "", 
34                         IsDbGenerated = col.Attribute("IsDbGenerated") != null ? col.Attribute("IsDbGenerated").Value.ToLower() == "true" : false, 
35                         IsPrimaryKey = col.Attribute("IsPrimaryKey") != null ? col.Attribute("IsPrimaryKey").Value.ToLower() == "true" : false, 
36                         Name = col.Attribute("Name") != null ? col.Attribute("Name").Value : "" 
37                     }; 
38                     t.Columns.Add(c); 
39                 } 
40 
41                 var ass = tab.Element(XName.Get("Type", "http://schemas.microsoft.com/linqtosql/dbml/2007%22)).Elements(XName.Get(%22Association%22, "http://schemas.microsoft.com/linqtosql/dbml/2007%22)); 
42                 foreach (var item in ass) 
43                 { 
44                     DBAssociation a = new DBAssociation() 
45                     { 
46                         Name = item.Attribute("Name") != null ? item.Attribute("Name").Value : "", 
47                         OtherKey = item.Attribute("OtherKey") != null ? item.Attribute("OtherKey").Value : "", 
48                         ThisKey = item.Attribute("ThisKey") != null ? item.Attribute("ThisKey").Value : "", 
49                         IsForeignKey = item.Attribute("IsForeignKey") != null ? item.Attribute("IsForeignKey").Value.ToLower() == "true" : false 
50                     }; 
51                     t.Associations.Add(a); 
52                 } 
53                 collection.Add(t); 
54             } 
55             return collection; 
56         } 
57 
58         #endregion 
59     } 
60 }
61 
62 

   在转化为我们的实体类，我们剩下的就是编写我们的CodeSmith模板了（更多知识可以参考CodeSmith模板）：

 1 <%@ CodeTemplate Language="C#" TargetLanguage="Text" Src="" Inherits="" Debug="False" Description="Template description here." %> 
 2 
 3 <%@ Import NameSpace="System" %> 
 4 <%@ Import NameSpace="System.Xml" %> 
 5 <%@ Import NameSpace="System.Text" %> 
 6 <%@ Import NameSpace="System.Collections.Generic" %> 
 7 <%@ Assembly Name="DbmlToTable" %> 
 8 
 9 --Code By Wolf 
10 <script runat="template"> 
11 private List<DbmlToTable.DBTable> _DbTableCollection; 
12 public List<DbmlToTable.DBTable> DbTableCollection 
13 { 
14     get 
15     { 
16         return _DbTableCollection; 
17     } 
18     set    
19     { 
20         _DbTableCollection=value; 
21     } 
22 } 
23 
24 public  string GeneratorTableSql(List<DbmlToTable.DBTable> collection) 
25 { 
26     StringBuilder sb = new StringBuilder(); 
27     StringBuilder sbAssocation = new StringBuilder(); 
28     foreach (DbmlToTable.DBTable item in collection) 
29     { 
30         List<string> cols = new List<string>(); 
31         foreach (DbmlToTable.DBColumn  col in item.Columns) 
32         { 
33             cols.Add(string.Format("{0} {1} {2} ", col.Name, col.DBType, col.IsPrimaryKey ? "PRIMARY KEY " : "")); 
34         } 
35         sb.AppendFormat("\r\nCREATE TABLE {0} \r\n(\r\n{1}\r\n)", item.TableName, string.Join(",\r\n", cols.ToArray())); 
36 
37         foreach (DbmlToTable.DBAssociation ass in item.Associations) 
38         { 
39             if (ass.IsForeignKey) 
40             { 
41                 DbmlToTable.DBTable tab = DbmlToTable.DBTableHlper.GetAssociationTable(collection,ass.Name); 
42                 if (tab != null) 
43                 { 
44                     sbAssocation.AppendLine(); 
45                     sbAssocation.AppendFormat(@"ALTER TABLE {0}  WITH NOCHECK ADD  CONSTRAINT {1} FOREIGN KEY({2}) REFERENCES {3} ({4})", 
46                         item.TableName, "FK_" + ass.Name, ass.ThisKey, tab.TableName, ass.OtherKey); 
47                 } 
48             } 
49         } 
50     } 
51 
52     return sb.ToString() + "\r\n" + sbAssocation.ToString(); 
53 } 
54 </script> 
55 <%= this.GeneratorTableSql(_DbTableCollection) %>
56 
57 

    在codeSimth中我们建立了一个集合属性传递实体类DBTable和一个转化TSql辅助方法.

      在控制台调用编译模板以及输出：

 1 using System; 
 2 using System.Collections.Generic; 
 3 using System.Linq; 
 4 using System.Text; 
 5 
 6 namespace DbmlToTable 
 7 { 
 8     class Program 
 9     { 
10         static void Main(string[] args) 
11         { 
12             IDbTableCollectionHelper helper = new DbTableCollectionHelper(); 
13             List<DBTable> collection = helper. 
14                 Transport(System.Xml.Linq.XElement.
15 
16          Load(@"xxpath\MultipleDocument.Data\MultipleDocumentDB.dbml")); 
17 
18             CodeSmith.Engine.CodeTemplate template = CodeSimthTemplateHelper. 
19                 CompileTemplate(@"DBMLToTable.cst", w => Console.WriteLine(w)); 
20             if (template != null) 
21             { 
22                 CodeSimthTemplateHelper.AddPropertyParams(template, new { DbTableCollection = collection }); 
23                 string str = template.RenderToString(); 
24                 Console.WriteLine(str); 
25                 //System.IO.File.AppendAllText(@"D:\1.sql", str); 
26             } 
27             Console.Read(); 
28         }
29 
30 }
31 
32  
33 
34 

   在CodeSimth中就是这么简单，生成相应的模板代码（个人理解CodeSmith就是把代码作为字符串输出）。

在上面到我的CodeSmith模板编译辅助类，在上一篇通过代码生成机制实现强类型编程-CodeSmith版也有，在这里也附带上：需要引用CodeSmith.Engine.dll.

 1 using System; 
 2 
 3 using System.Collections.Generic; 
 4 
 5 using System.Linq; 
 6 
 7 using System.Text; 
 8 
 9 using CodeSmith.Engine; 
10 
11 using Wolf.NameValueDictionary; 
12 
13 namespace DbmlToTable 
14 
15 { 
16 
17 public class CodeSimthTemplateHelper 
18 
19 { 
20 
21      public static CodeTemplate CompileTemplate(string templateName, Action errorWriter) 
22 
23      { 
24 
25            CodeTemplateCompiler compiler = new CodeTemplateCompiler(templateName); compiler.Compile(); 
26 
27           if (compiler.Errors.Count == 0) 
28 
29            { 
30 
31            return compiler.CreateInstance();
32 
33            } 
34 
35        else 
36 
37          { 
38 
39            for (int i = 0; i < compiler.Errors.Count; i++) 
40 
41         { 
42 
43             errorWriter(compiler.Errors[i].ToString()); 
44 
45          } 
46 
47         return null; 
48 
49        } 
50 
51 } 
52 
53  
54 
55 public static void AddPropertyParams(CodeTemplate template,object param) 
56 
57 { 
58 
59       NameValueDictionary dict = new NameValueDictionary<object>(param);
60 
61        AddPropertyParams(template, dict);
62 
63 }
64 
65  
66 
67 public static void AddPropertyParams(CodeTemplate template, NameValueDictionary<object> param)
68 
69 {
70 
71           NameValueDictionary<object> dict = new NameValueDictionary<object>(param);
72 
73           foreach (var item in dict.Keys)
74 
75           {
76 
77                 template.SetProperty(item, dict[item]);
78 
79            }
80 
81 }
82 
83 }
84 
85 }
86