User defined functions (VB.Net / netframework)
Note
This demo is available in your FlexCel installation at <FlexCel Install Folder>\samples\vb\VS2022\netframework\20.Reports\95.User Defined Functions and also at https://github.com/tmssoftware/TMS-FlexCel.NET-demos/tree/master/vb/VS2022/netframework/Modules/20.Reports/95.User Defined Functions
Overview
Here we will see how to define a user function to calculate the number of orders by employee and shipper. This example is similar to the Pivot Tables example, but using only static normal cells.
Concepts
How to define user functions for non-standard needs. By the way: Try to define only as little user functions as you really need. User functions are on code, and a change on them means that you have to recompile the code.
We defined two ranges here, one horizontal and one vertical. The user defined function here will return a value for a couple of those values, allowing us to create a "static" pivot table.
Files
AssemblyInfo.vb
Imports System.Reflection
Imports System.Runtime.CompilerServices
'
' General Information about an assembly is controlled through the following
' set of attributes. Change these attribute values to modify the information
' associated with an assembly.
'
<Assembly: AssemblyTitle("")>
<Assembly: AssemblyDescription("")>
<Assembly: AssemblyConfiguration("")>
<Assembly: AssemblyCompany("")>
<Assembly: AssemblyProduct("")>
<Assembly: AssemblyCopyright("(c) 2002 - 2014 TMS Software")>
<Assembly: AssemblyTrademark("")>
<Assembly: AssemblyCulture("")>
'
' Version information for an assembly consists of the following four values:
'
' Major Version
' Minor Version
' Build Number
' Revision
'
' You can specify all the values or you can default the Revision and Build Numbers
' by using the '*' as shown below:
<Assembly: AssemblyVersion("6.2.1.0")>
'
' In order to sign your assembly you must specify a key to use. Refer to the
' Microsoft .NET Framework documentation for more information on assembly signing.
'
' Use the attributes below to control which key is used for signing.
'
' Notes:
' (*) If no key is specified, the assembly is not signed.
' (*) KeyName refers to a key that has been installed in the Crypto Service
' Provider (CSP) on your machine. KeyFile refers to a file which contains
' a key.
' (*) If the KeyFile and the KeyName values are both specified, the
' following processing occurs:
' (1) If the KeyName can be found in the CSP, that key is used.
' (2) If the KeyName does not exist and the KeyFile does exist, the key
' in the KeyFile is installed into the CSP and used.
' (*) In order to create a KeyFile, you can use the sn.exe (Strong Name) utility.
' When specifying the KeyFile, the location of the KeyFile should be
' relative to the project output directory which is
' %Project Directory%\obj\<configuration>. For example, if your KeyFile is
' located in the project directory, you would specify the AssemblyKeyFile
' attribute as [assembly: AssemblyKeyFile("..\\..\\mykey.snk")]
' (*) Delay Signing is an advanced option - see the Microsoft .NET Framework
' documentation for more information on this.
'
<Assembly: AssemblyDelaySign(False)>
<Assembly: AssemblyKeyFile("")>
<Assembly: AssemblyKeyName("")>
Form1.Designer.vb
Imports System.Collections
Imports System.ComponentModel
Imports System.IO
Imports System.Reflection
Imports FlexCel.Core
Imports FlexCel.XlsAdapter
Imports FlexCel.Report
Imports FlexCel.Demo.SharedData
Namespace UserDefinedFunctions
Partial Public Class mainForm
Inherits System.Windows.Forms.Form
''' <summary>
''' Required designer variable.
''' </summary>
Private components As System.ComponentModel.Container = Nothing
''' <summary>
''' Clean up any resources being used.
''' </summary>
Protected Overrides Sub Dispose(ByVal disposing As Boolean)
If disposing Then
If components IsNot Nothing Then
components.Dispose()
End If
End If
MyBase.Dispose(disposing)
End Sub
#Region "Windows Form Designer generated code"
''' <summary>
''' Required method for Designer support - do not modify
''' the contents of this method with the code editor.
''' </summary>
Private Sub InitializeComponent()
Me.button1 = New System.Windows.Forms.Button()
Me.saveFileDialog1 = New System.Windows.Forms.SaveFileDialog()
Me.label1 = New System.Windows.Forms.Label()
Me.btnCancel = New System.Windows.Forms.Button()
Me.SuspendLayout()
'
' button1
'
Me.button1.Anchor = (CType((System.Windows.Forms.AnchorStyles.Top Or System.Windows.Forms.AnchorStyles.Right), System.Windows.Forms.AnchorStyles))
Me.button1.BackColor = System.Drawing.Color.Green
Me.button1.ForeColor = System.Drawing.Color.White
Me.button1.Location = New System.Drawing.Point(152, 88)
Me.button1.Name = "button1"
Me.button1.Size = New System.Drawing.Size(112, 23)
Me.button1.TabIndex = 0
Me.button1.Text = "GO!"
Me.button1.UseVisualStyleBackColor = False
' Me.button1.Click += New System.EventHandler(Me.button1_Click)
'
' saveFileDialog1
'
Me.saveFileDialog1.Filter = "Excel Files|*.xls;*.xlsx;*.xlsm|Excel 97/2003|*.xls|Excel 2007|*.xlsx;*.xlsm|All files|*.*"
Me.saveFileDialog1.RestoreDirectory = True
'
' label1
'
Me.label1.Location = New System.Drawing.Point(24, 24)
Me.label1.Name = "label1"
Me.label1.Size = New System.Drawing.Size(288, 24)
Me.label1.TabIndex = 2
Me.label1.Text = "A Crosstab report using an user defined function."
'
' btnCancel
'
Me.btnCancel.Anchor = (CType((System.Windows.Forms.AnchorStyles.Top Or System.Windows.Forms.AnchorStyles.Right), System.Windows.Forms.AnchorStyles))
Me.btnCancel.BackColor = System.Drawing.Color.FromArgb((CInt((CByte(192)))), (CInt((CByte(0)))), (CInt((CByte(0)))))
Me.btnCancel.DialogResult = System.Windows.Forms.DialogResult.Cancel
Me.btnCancel.ForeColor = System.Drawing.Color.White
Me.btnCancel.Location = New System.Drawing.Point(272, 88)
Me.btnCancel.Name = "btnCancel"
Me.btnCancel.Size = New System.Drawing.Size(112, 23)
Me.btnCancel.TabIndex = 3
Me.btnCancel.Text = "Cancel"
Me.btnCancel.UseVisualStyleBackColor = False
' Me.btnCancel.Click += New System.EventHandler(Me.btnCancel_Click)
'
' mainForm
'
Me.AutoScaleDimensions = New System.Drawing.SizeF(6F, 13F)
Me.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font
Me.ClientSize = New System.Drawing.Size(416, 133)
Me.Controls.Add(Me.btnCancel)
Me.Controls.Add(Me.label1)
Me.Controls.Add(Me.button1)
Me.Name = "mainForm"
Me.Text = "User defined functions"
Me.ResumeLayout(False)
End Sub
#End Region
Private WithEvents button1 As System.Windows.Forms.Button
Private saveFileDialog1 As System.Windows.Forms.SaveFileDialog
Private label1 As System.Windows.Forms.Label
Private WithEvents btnCancel As System.Windows.Forms.Button
End Class
End Namespace
Form1.vb
Imports System.Collections
Imports System.ComponentModel
Imports System.IO
Imports System.Reflection
Imports FlexCel.Core
Imports FlexCel.XlsAdapter
Imports FlexCel.Report
Imports FlexCel.Demo.SharedData
Namespace UserDefinedFunctions
Partial Public Class mainForm
Inherits System.Windows.Forms.Form
Public Sub New()
InitializeComponent()
End Sub
Private Sub button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles button1.Click
AutoRun()
End Sub
Public Sub AutoRun()
Using ordersReport As FlexCelReport = SharedData.CreateReport()
ordersReport.SetValue("Date", Date.Now)
ordersReport.SetUserFunction("Orders", New OrdersImp(SharedData.GetOrders()))
Dim DataPath As String = Path.Combine(Path.Combine(Path.GetDirectoryName(System.Reflection.Assembly.GetExecutingAssembly().Location), ".."), "..") & Path.DirectorySeparatorChar
If saveFileDialog1.ShowDialog() = System.Windows.Forms.DialogResult.OK Then
ordersReport.Run(DataPath & "User Defined Functions.template.xls", saveFileDialog1.FileName)
If MessageBox.Show("Do you want to open the generated file?", "Confirm", MessageBoxButtons.YesNo) = System.Windows.Forms.DialogResult.Yes Then
Process.Start(saveFileDialog1.FileName)
End If
End If
End Using
End Sub
Private Sub btnCancel_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnCancel.Click
Close()
End Sub
End Class
#Region "Orders Implementation"
Friend Class OrdersImp
Inherits TFlexCelUserFunction
Private OrdersDv As DataView
Public Sub New(ByVal OrdersTable As DataTable)
OrdersDv = New DataView(OrdersTable, String.Empty, "EmployeeID,ShipVia", DataViewRowState.CurrentRows)
End Sub
Public Overrides Function Evaluate(ByVal parameters() As Object) As Object
If parameters Is Nothing OrElse parameters.Length <> 2 Then
Throw New ArgumentException("Bad parameter count in call to Orders() user-defined function")
End If
Dim Count As Integer = OrdersDv.FindRows(parameters).Length
If Count > 0 Then
Return Count
Else
Return Nothing
End If
End Function
End Class
#End Region
End Namespace
Program.vb
Namespace UserDefinedFunctions
Friend NotInheritable Class Program
Private Sub New()
End Sub
''' <summary>
''' The main entry point for the application.
''' </summary>
<STAThread> _
Shared Sub Main()
Application.EnableVisualStyles()
Application.SetCompatibleTextRenderingDefault(False)
Application.Run(New mainForm())
End Sub
End Class
End Namespace