Abstract: N-Tiers development mode (how to use VB.NET to write a COM + component)
Small meow written COM + components began in VB6 years of writing and registered way still is not very complicated, but with the entry of the .NET world, the process of writing has become a lot more complicated.
Here are the steps written
It is assumed to be written in a database DDMO data table (TDMOMenu) data access component, to produce a component Package Name Services for KDMO1000 [], which has two inner components PDMOMenu.dll COM + components are
Project.Class
- PDMOMenu.CDMOMenu1 (no Transaction): for reading data
- PDMOMenu.CDMOMenu2 (there Transaction): to maintain data
Write steps:
Imports System.Runtime.InteropServices
Imports System.Data.SqlClient
Imports System.Data
Imports System.IO
_
Public Class CDMODEMO1
Inherits ServicedComponent
Const DBName as String = "DDMO"
Public Function Test1(ByVal In1() As String, ByVal Out1() As String, ByRef P As String, ByRef R As String, ByVal RUser As String) As String
'*
' 撰写者：topcat(topcat) 撰写日期：2008/7/23
' 用途： 1.
' 做法：
' 1.
' 注意事项：
' 1.
' 2.
' 维护记录：
' 维护者：姓名(员工代号) 维护日期：日期
' 维护项目：
' 1.
' 2.
' 做法： 1.
' 2.
' 注意事项：
' 1.
'*
Dim ConnStr As String = GetConnStr(DBName)
Try
Test1 = "Success"
Catch ex As Exception
Test1 = "False"
Throw New Exception(ex.Message)
Finally
End Try
End Function
Public Function GetConnStr(ByVal DBName As String) As String
'*
' 撰写者：topcat(topcat) 撰写日期：2006/2/8
' 用途： 1.读取Connection String的方式
' 做法：
' 1.传入参数DataBase Name DBName
' 2.透过Stream将文字档读出
' 3.将取得的数据返回
' 4.关闭相关对象
' 注意事项：
' 1.
' 2.
' 维护记录：
' 维护者：姓名(员工代号) 维护日期：日期
' 维护项目：
' 1.
' 2.
' 做法： 1.
' 2.
' 注意事项：
' 1.
'*
Dim StrmRd As New StreamReader("C:DataLink" + DBName + ".ini")
Dim Line As String = ""
Dim ConnStr As String = ""
Try
Do
Line = StrmRd.ReadLine()
If Line <> "" Then
ConnStr += Line
End If
Loop Until Line Is Nothing
GetConnStr = ConnStr
Catch ex As Exception
Throw New Exception(ex.Message.ToString)
Finally
StrmRd.Close()
StrmRd.Dispose()
StrmRd = Nothing
End Try
End Function
End Class
Imports System.Runtime.InteropServices
Imports System.Data.SqlClient
Imports System.Data
Imports System.IO
_
Public Class CDMODEMO2
Inherits ServicedComponent
Const DBName as String = "DDMO"
_
Public Function Test2(ByVal In1() As String, ByVal Out1() As String, ByRef P As String, ByRef R As String, ByVal RUser As String) As String
'*
' 撰写者：topcat(topcat) 撰写日期：2008/7/23
' 用途： 1.
' 做法：
' 1.
' 注意事项：
' 1.
' 2.
' 维护记录：
' 维护者：姓名(员工代号) 维护日期：日期
' 维护项目：
' 1.
' 2.
' 做法： 1.
' 2.
' 注意事项：
' 1.
'*
Dim ConnStr As String = GetConnStr(DBName)
Try
Test2 = "Success"
Catch ex As Exception
Test2 = "False"
Throw New Exception(ex.Message)
Finally
End Try
End Function
Public Function GetConnStr(ByVal DBName As String) As String
'*
' 撰写者：topcat(topcat) 撰写日期：2006/2/8
' 用途： 1.读取Connection String的方式
' 做法：
' 1.传入参数DataBase Name DBName
' 2.透过Stream将文字档读出
' 3.将取得的数据返回
' 4.关闭相关对象
' 注意事项：
' 1.
' 2.
' 维护记录：
' 维护者：姓名(员工代号) 维护日期：日期
' 维护项目：
' 1.
' 2.
' 做法： 1.
' 2.
' 注意事项：
' 1.
'*
Dim StrmRd As New StreamReader("C:DataLink" + DBName + ".ini")
Dim Line As String = ""
Dim ConnStr As String = ""
Try
Do
Line = StrmRd.ReadLine()
If Line <> "" Then
ConnStr += Line
End If
Loop Until Line Is Nothing
GetConnStr = ConnStr
Catch ex As Exception
Throw New Exception(ex.Message.ToString)
Finally
StrmRd.Close()
StrmRd.Dispose()
StrmRd = Nothing
End Try
End Function
End Class
- Construction project:
1. Where appropriate directory, create a directory of your project components [PDMOMenu]
2. Establish project (Create Project), select [library (Class Library)], set the directory to the directory of your project, name] is set to [PDMOMenu
3. program Explorer (Solution Explorer) in tap Class1.vb, change the file name (file name) properties (properties) in the range [CDMOMenu1.vb] (no TranSaction), [CDMOMenu2.vb ] (with the Transaction)
4. reference (reference) was added right → reference, increase System.EnterpriseServices []
→ step two
- Project Description:
1.点选项目(Project)右键→属性(Properties) 2.点选【签署(Signing)】，勾选【签署组件】 在选择强势名称金钥档(Choose a strong name key file) 选择新增(New)→输入【PDMOMenu】 3.点选【应用程序(Application)】 检查【组件名称(Assembly Name)】、【根命名空间(Root NameSpace)】是否是【PDMOMenu】 4.按【组件资讯】，将【让组件成为COM-Visiable(Make assembly COM-Visiable)】打勾 →步骤三 - AssemblyInfo.vb：
1.请在最上方Imports加入： Imports System.EnterpriseServices 2.请在最下方加入以操作： - Class content:
None Transaction Class (CDMOMenu1.vb): -
有Transaction Class(CDMOMenu2.vb)：
After writing about the program, followed by Build project, then it will have dll in accordance with the position of Project Property settings
Supplement, thanks to friends little magic to inform the content is wrong, get to make up the database connection Function
Description:
Data access will be through ConnString settings to specify which database is accessed on the Which Server, use the authentication is in what way. If ConnString written in the assembly, then when the Server address change, even change the name of the database, then we have to program components called out one by one to modify, and then compile registration, this process is too complicated
So how to set ConnString detached components, small meow approach is to create a .ini text file, on the C: DataLink, which stood on the content ConnString, and then read through the assembly System.IO the contents of text files.
Thus, in the future there is a database transaction (position, name), you may not need to rewrite components, directly modify configuration files.
The following is the signature:
- Welcome to the site posted the article, but the gist of your posts on the plus - posted, and attach Benpian hyperlinks station name in the article [topcat extreme cohesion between the Shan dance], thanks you for your cooperation.
- Most small meow meow small article will be familiar language to write VB.NET, C # if you need the Code, perhaps you can try online conversion tool, providing several reference here
- http://converter.telerik.com/
- http://www.carlosag.net/tools/codetranslator/
- http://www.developerfusion.com/tools/convert/vb-to-csharp/
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Original: Big Box N-Tiers development mode (how to use VB.NET to write a COM + component)