Access to SqlLite converter. VB example of Generic, Func, Extension. Using MS.ACE.OLEDB provider and SQLite.
This is simplest console application, I have publish is to https://github.com/Alex-1557/Access2SQLiteConverter.
Maybe for beginners can be interesting how I use Relection, Func, Generic. Please look to my code.
1: Imports System.Data.Common
2: Public Module RawSqlQuery
3: <Runtime.CompilerServices.Extension>
4: Public Function RawSqlQuery(Of T)(Connection As OleDb.OleDbConnection, ByVal SqlQuery As String, ByVal RowMapperFunc As Func(Of OleDb.OleDbDataReader, T), Optional NeedPrint As Boolean = True) As List(Of T)
5: Try
6: If NeedPrint Then
7: Dim Prop1 = GetType(T).GetProperties()
8: Dim Res1 As New List(Of String)
9: Prop1.ToList.ForEach(Sub(Y) Res1.Add(Y.Name))
10: Console.WriteLine(String.Join("#", Res1))
11: End If
12:
13: Using Command = New OleDb.OleDbCommand
14: Command.CommandText = SqlQuery
15: Command.CommandType = CommandType.Text
16: Command.Connection = Connection
17:
18: Using RDR = Command.ExecuteReader()
19: Dim ResultList = New List(Of T)()
20:
21: While RDR.Read()
22:
23: Dim X = RowMapperFunc(RDR)
24: ResultList.Add(X)
25:
26: If NeedPrint Then
27: Dim Prop2 = X.GetType().GetProperties()
28: Dim Res2 As New List(Of String)
29: Prop2.ToList.ForEach(Sub(Y)
30: If Y.PropertyType.Name = "Byte[]" Then
31: Res2.Add("*BYTE ARRAY*")
32: Else
33: Res2.Add(Y.GetValue(X, Nothing))
34: End If
35:
36: End Sub)
37: Console.WriteLine(String.Join("#", Res2))
38: End If
39:
40: End While
41:
42: Return ResultList
43: End Using
44: End Using
45: Catch ex As Exception
46: Console.WriteLine($" Error: {ex.Message} : in {SqlQuery}")
47: Return Nothing
48: End Try
49: End Function
50:
51: End Module
1: Module CheckDBNull
2: <Runtime.CompilerServices.Extension>
3: Public Function CheckDBNull(Of T)(ByVal DbField As Object) As T
4: If DbField Is Nothing OrElse DbField Is DBNull.Value Then
5: Return Nothing
6: Else
7: Return CType(DbField, T)
8: End If
9:
10: End Function
11:
12: End Module
Access context:
Sql context:
WinDesktop context:
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