代码改变世界

CodeDom六--实体类生成示例

2010-07-08 10:15  破狼  阅读(4193)  评论(25编辑  收藏  举报

      CodeDom这个东西个人觉得知识点不多,前几个续节写的已差不多了。在这节将演示一个CodeDom示例:

数据库实体类的生成。这里先声明在如今的CodeSmith或者是T4模板中实现这些都很简单,并且更实用,在这

里只是一个CodeDom示例,为了演示CodeDom。

      在代码中位了简单、简化数据库数据信息的提取,引用了CodeSimth的SchemaExplorer.dll和SchemaExplorer.

SqlSchemaProvider.dll。可以在Demo中的CodeSimth目录下找到。

      先贴上代码,需要讲解的东西没有什么:

using System;
using System.Text;
using System.Windows.Forms;
using SchemaExplorer;
using System.CodeDom;
using System.CodeDom.Compiler;
namespace CodeDomDemo
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
IDbSchemaProvider provider = new SqlSchemaProvider();
string connectionString = System.Configuration.ConfigurationManager.
AppSettings["ConnectionString"].ToString();
if (string.IsNullOrEmpty(connectionString))
{
MessageBox.Show(this, "Connection String is requested,in app configuration.",
 "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
Application.Exit();
}
DatabaseSchema db = new DatabaseSchema(provider, connectionString);
lboxTables.Items.AddRange(db.Tables.ToArray());
}
        public CodeCompileUnit GenTableCompilerUnit(TableSchema item)
{
if (item == null)
throw new ArgumentNullException("item");
CodeTypeDeclaration tableClass = new CodeTypeDeclaration();
tableClass.Attributes = MemberAttributes.Public | MemberAttributes.Final;
tableClass.Name = item.Name;
            foreach (var col in item.Columns)
{
CodeMemberField field = new CodeMemberField(
new CodeTypeReference(col.SystemType), "_" + col.Name);
CodeMemberProperty property = new CodeMemberProperty();
property.Name = col.Name;
property.Attributes = MemberAttributes.Public | MemberAttributes.Final;
property.Type = new CodeTypeReference(col.SystemType);
property.SetStatements.Add(new CodeAssignStatement(
new CodeFieldReferenceExpression(new CodeThisReferenceExpression(),
field.Name), new CodePropertySetValueReferenceExpression()));
property.GetStatements.Add(new CodeMethodReturnStatement(
new CodeFieldReferenceExpression(new CodeThisReferenceExpression(), field.Name)));
tableClass.Members.Add(field);
tableClass.Members.Add(property);
}
CodeNamespace nspace = new CodeNamespace(item.Database.Name);
nspace.Imports.Add(new CodeNamespaceImport("System"));
nspace.Types.Add(tableClass);
CodeCompileUnit unit=new CodeCompileUnit();
unit.Namespaces.Add(nspace);
return unit;
}
public string GenTanleCodeFromCompilerUnit(CodeCompileUnit unit, string language)
{
CodeGeneratorOptions option=new CodeGeneratorOptions();
option.BlankLinesBetweenMembers =true;
option.BracingStyle ="c";
option.ElseOnClosing=true;
option.IndentString="    ";
StringBuilder sb=new StringBuilder();
System.IO.StringWriter sw=new System.IO.StringWriter(sb);
CodeDomProvider.CreateProvider(language).GenerateCodeFromCompileUnit(unit, sw, option);
sw.Close();
return sb.ToString();
}
        private void lboxTables_SelectedIndexChanged(object sender, EventArgs e)
{
int index = lboxTables.SelectedIndex;
if (index > -1 && index < lboxTables.Items.Count)
{
object obj = lboxTables.Items[index];
if (obj is TableSchema)
{
CodeCompileUnit unit= GenTableCompilerUnit(obj as TableSchema);
string language="c#";
if(!string.IsNullOrEmpty(this.toolStripComboBox1.Text))
language=this.toolStripComboBox1.Text;
string code = GenTanleCodeFromCompilerUnit(unit,language);
this.rtbCode.Text = code;
}
}
}
}
}
运行示图:c#图
imagec#图

vb图:

imagevb图

               代码比较简单界面也做得太简洁了,呵呵导出文件都没有,我觉得没有什么必要讲解的,如果有什么不懂的或者是写的不对

       不好的,请留言,我会尽快回复。

CodeDom代码下载;