Manipulating an Image Data in Visual F#

To manipulate an image data, simply add an oleobject fieldname on your table and insert a bitmap image to it. To display the image on your form, use a picturebox control then bind your oleobject fieldname to it using the following syntax:
Pictureboxobjname.DataBindings.Add(new Binding(pictureboxproperty,datasource,fieldname))
For instance:
appico.DataBindings.Add(new Binding("Image",bindingsource,"oleapplogo",true))
The last boolean parameter enables the control formatting. We also use the Image property instead of the usual Text for the fact that it is the property used to display an image on your form.

Before proceding to the steps below, I want you to make an Ms-Access 2003 or 2007 database file named “dbApplication”. Create a table inside it and name it “tblApplication”. Use the following specifications:



Chrappname Text Handles the application name
Oleapplogo OLE Object Handles the application ico

After creating your table, you can add appropriate values to it for instance:




chrappname oleapplogo
PHP Bitmap Image
Apache Bitmap Image

Bitmap Image refers the the Bitmap Object that you have inserted using the Paste From Ms-Paint command.

After creating the table and adding appropriate values to it.We are now ready for our sample application. Just follow these steps:

1. Click Start>All Programs>Microsoft Visual Studio 2008>Microsoft Visual Studio 2008.

2. Click File>New>Project>Select Visual F# in the project types>Select F# application in the Visual Studio installed templates category.

3. Click the Project menu>Add reference>Click the .Net tab>Locate then double-click System.Windows.Forms. Do step 3 again and this time, select System.Drawing and System.Data from the .Net tab.

4. Enter the following code after the line “// Learn more about F# at http://fsharp.net “:

// Learn more about F# at http://fsharp.net
//specifies the memory location of the class files
//that will be needed in our application
open System
open System.Windows.Forms
open System.Data
open System.Drawing
//creates a font
let ffont=new Font("Verdana", 9.75F,FontStyle.Regular, GraphicsUnit.Point)  
//creates a connection object
let oleconn = new System.Data.OleDb.OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;
  Data Source=C:\Documents and Settings\station 2\My Documents\dbApplication.mdb")
 //creates an OleDbDataAdapter
let dataadpter = new System.Data.OleDb.OleDbDataAdapter("Select * from tblApplication", oleconn)
//generates a dataset
let dataset11 = new DataSet()
//fills the dataset with recod values
dataadpter.Fill(dataset11,"tblApplication")|>ignore
//creates a form
let dataform = new Form(Text="Manipulate Image Data",AutoScaleDimensions=new System.Drawing.SizeF(60.0F, 13.0F),ClientSize=new System.Drawing.Size(300, 200),StartPosition=FormStartPosition.CenterScreen)
//creates our controls  
let label1=new Label(Text="App. name:",Location=new System.Drawing.Point(0, 10),AutoSize=true)
let label2=new Label(Text="Icon:",Location=new System.Drawing.Point(0, 50),AutoSize=true)
let appnamelabel=new Label(Location=new System.Drawing.Point(140,10),BorderStyle=BorderStyle.FixedSingle)
let appico=new PictureBox(SizeMode=PictureBoxSizeMode.StretchImage,Location=new System.Drawing.Point(140,50))

let bindingsource=new BindingSource()
//creates a binding navigator
//this will allow us to add navigational buttons to our data grid
let bindingnav=new BindingNavigator(Dock=DockStyle.None,Location=new System.Drawing.Point(100, 170))
//creates a toolstrip buttons for our binding navigator
let movefirst=new ToolStripButton(Text="Top")
let moveprev=new ToolStripButton(Text="Prev")
let movenext=new ToolStripButton(Text="Next")
let movelast=new ToolStripButton(Text="Bottom")
let exitbutton=new ToolStripButton(Text="Exit")
//adds the toolstripbuttons to our binding navigator
bindingnav.Items.Add(movefirst)|>ignore
bindingnav.Items.Add(moveprev)|>ignore
bindingnav.Items.Add(movenext)|>ignore
bindingnav.Items.Add(movelast)|>ignore
bindingnav.Items.Add(exitbutton)|>ignore
//adds a function to each buttons
bindingnav.MoveFirstItem<-movefirst
bindingnav.MoveNextItem<-movenext
bindingnav.MovePreviousItem<-moveprev
bindingnav.MoveLastItem<-movelast
exitbutton.Click.Add(fun exit->
//close the form and dataconnection
                    dataform.Close()
                    oleconn.Close())
//assigns the dataset name as a bindingsource datasource
bindingsource.DataSource<-dataset11
//assigns our table as a binding source datamember
bindingsource.DataMember<-"tblApplication"
//assigns the bindingsource name as a binding navigators
//bindingsource value
bindingnav.BindingSource<-bindingsource
//opens the connection
oleconn.Open()
//assings the font to our form
dataform.Font<-ffont
//adds the controls to our form
dataform.Controls.Add(label1)
dataform.Controls.Add(label2)
dataform.Controls.Add(appnamelabel)
dataform.Controls.Add(appico)

dataform.Controls.Add(bindingnav)
//binds the fieldnames to our label
appnamelabel.DataBindings.Add(new Binding("Text",bindingsource,"chrappname"))
appico.DataBindings.Add(new Binding("Image",bindingsource,"oleapplogo",true))
//executes our application
dataform.Show()
Application.Run(dataform)
5. Click the run icon to execute your application. You should now see an output similar to the following screen shot: 6. Here’s another version of the code above without BindingSource and BindingNavigator.
// Learn more about F# at http://fsharp.net
//specifies the memory location of the class files
//that will be needed in our application
open System
open System.Windows.Forms
open System.Data
open System.Drawing
//creates a font
let ffont=new Font("Verdana", 9.75F,FontStyle.Regular, GraphicsUnit.Point)  
//creates a connection object
let oleconn = new System.Data.OleDb.OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;
  Data Source=C:\Documents and Settings\station 2\My Documents\dbApplication.mdb")
 //creates an OleDbDataAdapter
let dataadpter = new System.Data.OleDb.OleDbDataAdapter("Select * from tblApplication", oleconn)
//generates a dataset
let dataset11 = new DataSet()
//fills the dataset with recod values
dataadpter.Fill(dataset11,"tblApplication")|>ignore
//creates a form
let dataform = new Form(Text="Manipulate Image Data",AutoScaleDimensions=new System.Drawing.SizeF(60.0F, 13.0F),ClientSize=new System.Drawing.Size(300, 200),StartPosition=FormStartPosition.CenterScreen)
//creates our controls  
let label1=new Label(Text="App. name:",Location=new System.Drawing.Point(0, 10),AutoSize=true)
let label2=new Label(Text="Icon:",Location=new System.Drawing.Point(0, 50),AutoSize=true)
let appnamelabel=new Label(Location=new System.Drawing.Point(140,10),BorderStyle=BorderStyle.FixedSingle)
let appico=new PictureBox(SizeMode=PictureBoxSizeMode.StretchImage,Location=new System.Drawing.Point(140,50))
//opens the connection
oleconn.Open()
//assings the font to our form
dataform.Font<-ffont
//adds the controls to our form
dataform.Controls.Add(label1)
dataform.Controls.Add(label2)
dataform.Controls.Add(appnamelabel)
dataform.Controls.Add(appico)
//binds the fieldnames to our label
appnamelabel.DataBindings.Add(new Binding("Text",dataset11,"tblApplication.chrappname"))
appico.DataBindings.Add(new Binding("Image",dataset11,"tblApplication.oleapplogo",true))
//executes our application
dataform.Show()
Application.Run(dataform)
For more sketchy tutorials on Visual F# visit Microsoft F# Developer Center.

Adding navigational Buttons to your database application

The fastest way to add navigational buttons to your database application is to use a BindingNavigator. If you are not yet familiar with Binding Navigator, I suggest reading this post first before proceeding to the steps below:

Before the Database Connection and Binding process I want you to make an Ms-Access database file named “dbEmployee” containing a table named “tblEmployee”. Use the following specifications:

Field NameData Type Description
chrempno text Handles employee id
chrfnametext Handles employee’s name
chrlname text Holds employee’s last name


After designing the structure of your table, you can enter appropriate values for each field. For instance:

chrempnochrfnameChrlname
1John Doe
2Jean Doe


Now that we are done creating a table, we can now link to it by using OleDbDataAdapter in Visual F#:


1. Click Start>All Programs>Microsoft Visual Studio 2008>Microsoft Visual Studio 2008.

2. Click File>New>Project>Select Visual F# in the project types>Select F# application in the Visual Studio installed templates category.

3. Click the Project menu>Add reference>Click the .Net tab>Locate then double-click System.Windows.Forms. Do step 3 again and this time, select System.Drawing and System.Data from the .Net tab.

4. Enter the following code after the line “// Learn more about F# at http://fsharp.net “:

// Learn more about F# at http://fsharp.net
//specifies the memory location of the class files
//that will be needed in our application
open System
open System.Windows.Forms
open System.Data
open System.Drawing
//creates a font
let ffont=new Font("Verdana", 9.75F,FontStyle.Regular, GraphicsUnit.Point)  
//creates a connection object
let oleconn = new System.Data.OleDb.OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;
  Data Source=C:\Documents and Settings\station 2\My Documents\dbEmployee.mdb")
 //creates an OleDbDataAdapter
let dataadpter = new System.Data.OleDb.OleDbDataAdapter("Select * from tblEmployee", oleconn)
//generates a dataset
let dataset11 = new DataSet()
//fills the dataset with recod values
dataadpter.Fill(dataset11,"tblEmployee")|>ignore
//creates a form
let dataform = new Form(Text="Add Navigational Buttons",AutoScaleDimensions=new System.Drawing.SizeF(60.0F, 13.0F),ClientSize=new System.Drawing.Size(300, 200),StartPosition=FormStartPosition.CenterScreen)
//creates our controls  
let label1=new Label(Text="Employee number:",Location=new System.Drawing.Point(0, 10),AutoSize=true)
let label2=new Label(Text="Firstname:",Location=new System.Drawing.Point(0, 50),AutoSize=true)
let label3=new Label(Text="Lastname:",Location=new System.Drawing.Point(0,100),AutoSize=true)
let emplabel=new Label(Location=new System.Drawing.Point(140,10),BorderStyle=BorderStyle.FixedSingle)
let fnamelabel=new Label(Location=new System.Drawing.Point(100,50),BorderStyle=BorderStyle.FixedSingle)
let lnamelabel=new Label(Location=new System.Drawing.Point(100,100),BorderStyle=BorderStyle.FixedSingle)
let bindingsource=new BindingSource()
//creates a binding navigator
//this will allow us to add navigational buttons to our data grid
let bindingnav=new BindingNavigator(Dock=DockStyle.None,Location=new System.Drawing.Point(100, 170))
//creates a toolstrip buttons for our binding navigator
let movefirst=new ToolStripButton(Text="Top")
let moveprev=new ToolStripButton(Text="Prev")
let movenext=new ToolStripButton(Text="Next")
let movelast=new ToolStripButton(Text="Bottom")
let exitbutton=new ToolStripButton(Text="Exit")
//adds the toolstripbuttons to our binding navigator
bindingnav.Items.Add(movefirst)|>ignore
bindingnav.Items.Add(moveprev)|>ignore
bindingnav.Items.Add(movenext)|>ignore
bindingnav.Items.Add(movelast)|>ignore
bindingnav.Items.Add(exitbutton)|>ignore
//adds a function to each buttons
bindingnav.MoveFirstItem<-movefirst
bindingnav.MoveNextItem<-movenext
bindingnav.MovePreviousItem<-moveprev
bindingnav.MoveLastItem<-movelast
exitbutton.Click.Add(fun exit->
//close the form and dataconnection
                    dataform.Close()
                    oleconn.Close())
//assigns the dataset name as a bindingsource datasource
bindingsource.DataSource<-dataset11
//assigns our table as a binding source datamember
bindingsource.DataMember<-"tblEmployee"
//assigns the bindingsource name as a binding navigators
//bindingsource value
bindingnav.BindingSource<-bindingsource
//opens the connection
oleconn.Open()
//assings the font to our form
dataform.Font<-ffont
//adds the controls to our form
dataform.Controls.Add(label1)
dataform.Controls.Add(label2)
dataform.Controls.Add(label3)
dataform.Controls.Add(emplabel)
dataform.Controls.Add(fnamelabel)
dataform.Controls.Add(lnamelabel)
dataform.Controls.Add(bindingnav)
//binds the fieldnames to our label
emplabel.DataBindings.Add(new Binding("Text",bindingsource,"chrempno"))
fnamelabel.DataBindings.Add(new Binding("Text",bindingsource,"chrfname"))
lnamelabel.DataBindings.Add(new Binding("Text",bindingsource,"chrlname"))
//executes our application
dataform.Show()
Application.Run(dataform)
5. Click the run icon to execute your application. You should now see an output similar to the following screen shot: For more sketchy tutorials on Visual F# visit Microsoft F# Developer Center.

BindingSource and BindingNavigator(OleDbDataAdapter Visual F#)

BindingSource allows us to simplify the binding process to our control. To create a binding source in Visual F#, use the following syntax:
let bindingsourceobjname=new BindingSource()
for instance:
let bindingsource=new BindingSource()
The two most important properties of BindingSource component are DataSource which specifies the data source of the bindingsource, and the Datamember which specifies the specific table to which your bindingsource is bound to.

BindingNavigator are simply used to add navigational buttons to your database application. The syntax in creating a binding source is:
let bindingnavigatorobjvariable=new BindingNavigator()
for instance:
let bindingnav=new BindingNavigator()
One of the essential properties of the BindingNavigator component is the BindingSource which specifies the bindingsource name to which the BindingNavigator is bound to.

Follow these steps for a simple example on using binding navigator:

Before the Database Connection and Binding process I want you to make an Ms-Access database file named “dbEmployee” containing a table named “tblEmployee”. Use the following specifications:

Field NameData Type Description
chrempno text Handles employee id
chrfnametext Handles employee’s name
chrlname text Holds employee’s last name


After designing the structure of your table, you can enter appropriate values for each field. For instance:

chrempnochrfnameChrlname
1John Doe
2Jean Doe


Now that we are done creating a table, we can now link to it by using OleDbDataAdapter in Visual F#:


1. Click Start>All Programs>Microsoft Visual Studio 2008>Microsoft Visual Studio 2008.

2. Click File>New>Project>Select Visual F# in the project types>Select F# application in the Visual Studio installed templates category.

3. Click the Project menu>Add reference>Click the .Net tab>Locate then double-click System.Windows.Forms. Do step 3 again and this time, select System.Drawing and System.Data from the .Net tab.

4. Enter the following code after the line “// Learn more about F# at http://fsharp.net “:

// Learn more about F# at http://fsharp.net
//specifies the location of the class files
//that will be needed in our application
open System
open System.Windows.Forms
open System.Data
open System.Drawing
//creates a connection object
let olecon = new System.Data.OleDb.OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;
  Data Source=C:\Documents and Settings\Administrator\My Documents\dbEmployee.mdb")
//adds an oleDbDataAdapter
let dataadapter = new System.Data.OleDb.OleDbDataAdapter("Select * from tblEmployee", olecon)
//generate a dataset
let dataset11 = new DataSet()
//fill our dataset with record values
dataadapter.Fill(dataset11,"tblEmployee")|>ignore
//creates a form
let dataform = new Form(Text="Change DataGrid Header",ClientSize=new System.Drawing.Size(398, 232))
//creates a datagrid
let datagrid = new DataGridView(ColumnHeadersHeightSizeMode=DataGridViewColumnHeadersHeightSizeMode.AutoSize,Size=new System.Drawing.Size(341, 143),Location=new System.Drawing.Point(22, 38))
//creates a binding source to simplify the binding process
let bindingsource=new BindingSource()
//creates a binding navigator
//this will allow us to add navigational buttons to our data grid
let bindingnav=new BindingNavigator()
//creates a toolstrip buttons for our binding navigator
let movefirst=new ToolStripButton(Text="Top")
let moveprev=new ToolStripButton(Text="Prev")
let movenext=new ToolStripButton(Text="Next")
let movelast=new ToolStripButton(Text="Bottom")
//adds the toolstripbuttons to our binding navigator
bindingnav.Items.Add(movefirst)|>ignore
bindingnav.Items.Add(moveprev)|>ignore
bindingnav.Items.Add(movenext)|>ignore
bindingnav.Items.Add(movelast)|>ignore
//adds a function to each buttons
bindingnav.MoveFirstItem<-movefirst
bindingnav.MoveNextItem<-movenext
bindingnav.MovePreviousItem<-moveprev
bindingnav.MoveLastItem<-movelast
//assigns the dataset name as a bindingsource datasource
bindingsource.DataSource<-dataset11
//assigns our table as a binding source datamember
bindingsource.DataMember<-"tblEmployee"
//assigns the bindingsource name as a binding navigators
//bindingsource value
bindingnav.BindingSource<-bindingsource
//opens the connection
olecon.Open()
//adds the controls to our form
dataform.Controls.Add(bindingnav)
datagrid.DataSource <- bindingsource

//add the datagrid to our form
dataform.Controls.Add(datagrid)
//execute our application
dataform.Show()
Application.Run(dataform)
5. Click the run icon to execute your application. You should now see an output similar to the following screen shot: For more sketchy tutorials on Visual F# visit Microsoft F# Developer Center.

Changing the DataGridView Header Text in Visual F#

To change the header text of a grid contrl in Visual F#, the first thing that you’ll need to do is to create a grid view columns. This can be done by using the following syntax:
let columnname=new DataGridViewTextBoxColumn()
For instance:
let chrempnocol=new DataGridViewTextBoxColumn()
After that, you’ll need to add that column to the data grid. This can be done by using the following syntax:
dataobjvariable.Columns.Add(columnname)
For example:
datagrid.Columns.Add(chrempnocol)
Then finally, you’ll need to bind the column name to the fieldname where you will be getting the record value followed by changing its header text using the DataPropertyName and HeaderText propeties.

For a simple example on changing the header text of a grid control, follow these steps:

Before the Database Connection and Binding process I want you to make an Ms-Access database file named “dbEmployee” containing a table named “tblEmployee”. Use the following specifications:

Field NameData Type Description
chrempno text Handles employee id
chrfnametext Handles employee’s name
chrlname text Holds employee’s last name


After designing the structure of your table, you can enter appropriate values for each field. For instance:

chrempnochrfnameChrlname
1John Doe
2Jean Doe


Now that we are done creating a table, we can now link to it by using OleDbDataAdapter in Visual F#:


1. Click Start>All Programs>Microsoft Visual Studio 2008>Microsoft Visual Studio 2008.

2. Click File>New>Project>Select Visual F# in the project types>Select F# application in the Visual Studio installed templates category.

3. Click the Project menu>Add reference>Click the .Net tab>Locate then double-click System.Windows.Forms. Do step 3 again and this time, select System.Drawing and System.Data from the .Net tab.

4. Enter the following code after the line “// Learn more about F# at http://fsharp.net “:

// Learn more about F# at http://fsharp.net
//specifies the location of the class files
//that will be needed in our application
open System
open System.Windows.Forms
open System.Data
open System.Drawing
//creates a connection object
let olecon = new System.Data.OleDb.OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;
  Data Source=C:\Documents and Settings\Administrator\My Documents\dbEmployee.mdb")
//adds an oleDbDataAdapter
let dataadapter = new System.Data.OleDb.OleDbDataAdapter("Select * from tblEmployee", olecon)
//generate a dataset
let dataset11 = new DataSet()
//fill our dataset with record values
dataadapter.Fill(dataset11,"tblEmployee")|>ignore
//creates a form
let dataform = new Form(Text="Change DataGrid Header",ClientSize=new System.Drawing.Size(398, 232))
//creates a datagrid
let datagrid = new DataGridView(ColumnHeadersHeightSizeMode=DataGridViewColumnHeadersHeightSizeMode.AutoSize,Size=new System.Drawing.Size(341, 143),Location=new System.Drawing.Point(22, 38))
//creates a grid control colums
let chrempnocol=new DataGridViewTextBoxColumn()
let chrfnamecol=new DataGridViewTextBoxColumn()
let chrlnamecol=new DataGridViewTextBoxColumn()
//adds the columns into our datagrid
datagrid.Columns.Add(chrempnocol)|>ignore
datagrid.Columns.Add(chrfnamecol)|>ignore
datagrid.Columns.Add(chrlnamecol)|>ignore
//opens the database connection and
//set our table as the datagrid's datasource
olecon.Open()
datagrid.DataSource <- dataset11.Tables.["tblEmployee"]
//links our fieldname to each grid
//and change its header text
chrempnocol.DataPropertyName<-"chrempno"
chrempnocol.HeaderText<-"Employee No."
chrfnamecol.DataPropertyName<-"chrfname"
chrfnamecol.HeaderText<-"First Name"
chrlnamecol.DataPropertyName<-"chrlname"
chrlnamecol.HeaderText<-"Last Name"
//add the datagrid to our form
dataform.Controls.Add(datagrid)
//execute our application
dataform.Show()
Application.Run(dataform)
5. Click the run icon to execute your application. You should now see an output similar to the following screen shot:
For more sketchy tutorials on Visual F# visit Microsoft F# Developer Center.That's all for now:)

Binding a Record Value To a Control (OleDbDataAdapter Visual F#)

To bind a record value to a control, simply use the DataBindings method of the control which has the following syntax:

controlobjvariable.DataBindings.Add(new Binding(controlproperty, datasetname, fieldname))
For instance:

fnamelabel.DataBindings.Add(new Binding("Text", dataset11, "Table1.fname", true))
For a simple data binding example, follow these steps:

Before the Database Connection and Binding process I want you to make an Ms-Access database file named “dbEmployee” containing a table named “tblEmployee”. Use the following specifications:

Field NameData Type Description
chrempno text Handles employee id
chrfnametext Handles employee’s name
chrlname text Holds employee’s last name


After designing the structure of your table, you can enter appropriate values for each field. For instance:

chrempnochrfnameChrlname
2010AJohn Doe
2010BJean Doe


Now that we are done creating a table, we can now link to it by using OleDbDataAdapter in Visual F#:


1. Click Start>All Programs>Microsoft Visual Studio 2008>Microsoft Visual Studio 2008.

2. Click File>New>Project>Select Visual F# in the project types>Select F# application in the Visual Studio installed templates category.

3. Click the Project menu>Add reference>Click the .Net tab>Locate then double-click System.Windows.Forms. Do step 3 again and this time, select System.Drawing and System.Data from the .Net tab.

4. Enter the following code after the line “// Learn more about F# at http://fsharp.net “:

// Learn more about F# at http://fsharp.net
//specifies the memory location of the class files
//that will be needed in our application
open System
open System.Windows.Forms
open System.Data
open System.Drawing
//creates a font
let ffont=new Font("Verdana", 9.75F,FontStyle.Regular, GraphicsUnit.Point)  
//creates a connection object
let oleconn = new System.Data.OleDb.OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;
  Data Source=C:\Documents and Settings\station 2\My Documents\dbEmployee.mdb")
 //creates an OleDbDataAdapter
let dataadpter = new System.Data.OleDb.OleDbDataAdapter("Select * from tblEmployee", oleconn)
//generates a dataset
let dataset11 = new DataSet()
//fills the dataset with recod values
dataadpter.Fill(dataset11,"tblEmployee")|>ignore
//creates a form
let dataform = new Form(Text="Use OleDbDataAdapter",AutoScaleDimensions=new System.Drawing.SizeF(60.0F, 13.0F),ClientSize=new System.Drawing.Size(300, 200),StartPosition=FormStartPosition.CenterScreen)
//creates our controls
let exitbutton=new Button(Text="Exit", Location=new System.Drawing.Point(190, 170))  
let label1=new Label(Text="Employee number:",Location=new System.Drawing.Point(0, 10),AutoSize=true)
let label2=new Label(Text="Firstname:",Location=new System.Drawing.Point(0, 50),AutoSize=true)
let label3=new Label(Text="Lastname:",Location=new System.Drawing.Point(0,100),AutoSize=true)
let emplabel=new Label(Location=new System.Drawing.Point(140,10),BorderStyle=BorderStyle.FixedSingle)
let fnamelabel=new Label(Location=new System.Drawing.Point(100,50),BorderStyle=BorderStyle.FixedSingle)
let lnamelabel=new Label(Location=new System.Drawing.Point(100,100),BorderStyle=BorderStyle.FixedSingle)
//assings the font to our form
dataform.Font<-ffont
//adds the controls to our form
dataform.Controls.Add(exitbutton)
dataform.Controls.Add(label1)
dataform.Controls.Add(label2)
dataform.Controls.Add(label3)
dataform.Controls.Add(emplabel)
dataform.Controls.Add(fnamelabel)
dataform.Controls.Add(lnamelabel)
//binds the fieldnames to our label
emplabel.DataBindings.Add(new Binding("Text",dataset11,"tblEmployee.chrempno"))
fnamelabel.DataBindings.Add(new Binding("Text",dataset11,"tblEmployee.chrfname"))
lnamelabel.DataBindings.Add(new Binding("Text",dataset11,"tblEmployee.chrlname"))
//when the exit button is clicked
exitbutton.Click.Add(fun exit->
//close the form and dataconnection
                    dataform.Close()
                    oleconn.Close())

//executes our application
dataform.Show()
Application.Run(dataform)

5. Click the run icon to execute your application. You should now see an output similar to the following screen shot:

Linking to an Ms-Access DataSource using OledbDataAdapter in Visual F#

To link to an Ms-Access data source, the first thing that you’ll need to do is to create an object variable based on the OleDbConnection class. OleDbConnection specifies the name of the Data Provider and the Location of the database file that you wish to link to. To create an OleDbConnection object use the following syntax:
let Oledbconnectionobjvariable = new System.Data.OleDb.OleDbConnection("Provider=DataProviderName;
Data Source=Url and filename of the database file")
For instance:
let Oledbconnectionobjvariable = new System.Data.OleDb.OleDbConnection("Provider= Microsoft.Jet.OLEDB.4.0;
Data Source=C:\Mydatabasefile.mdb")
Microsoft.Jet.OLEDB.4.0 is a data provider used to link to Ms-Access 2003 or higher database files.
After creating an OledbConnectionObject, the next thing that you’ll need to do is to add an OleDbDataAdapter control, to specify how the data will be displayed on your form and the information about the connection. This can be done by using the following syntax:
let oledbdataadapterobjvariable= new System.Data.OleDb. OleDbDataAdapter("SQL statement", ConnectionString)
ConnectionString refers to the information about the connection and is saved in the Oledbconnection object.

Lastly, youll need to create a storage location for your table values. This can be done by creating a Dataset. To create a dataset, use the following syntax:
Let Datasetobjvariable=new Dataset()
For a simple example on using OleDbDataAdapter to an AccessDataSource, follow these steps:

Before the Database Connection and Binding process I want you to make an Ms-Access database file named “dbEmployee” containing a table named “tblEmployee”. Use the following specifications:

Field NameData Type Description
chrempno text Handles employee id
chrfnametext Handles employee’s name
chrlname text Holds employee’s last name


After designing the structure of your table, you can enter appropriate values for each field. For instance:

chrempnochrfnameChrlname
2010AJohn Doe
2010BJean Doe


Now that we are done creating a table, we can now link to it by using OleDbDataAdapter in Visual F#:


1. Click Start>All Programs>Microsoft Visual Studio 2008>Microsoft Visual Studio 2008.

2. Click File>New>Project>Select Visual F# in the project types>Select F# application in the Visual Studio installed templates category.

3. Click the Project menu>Add reference>Click the .Net tab>Locate then double-click System.Windows.Forms. Do step 3 again and this time, select System.Drawing and System.Data from the .Net tab.

4. Enter the following code after the line “// Learn more about F# at http://fsharp.net “:

// Learn more about F# at http://fsharp.net
//specifies the memory location of the class files
//that will be needed in our application
open System
open System.Windows.Forms
open System.Data
open System.Drawing
//creates a font
let ffont=new Font("Verdana", 9.75F,FontStyle.Italic, GraphicsUnit.Point)  
//creates a connection object
let oleconn = new System.Data.OleDb.OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;
Data Source=C:\Documents and Settings\station 2\My Documents\dbEmployee.mdb")
//creates an OleDbDataAdapter
let dataadpter = new System.Data.OleDb.OleDbDataAdapter("Select * from tblEmployee", oleconn)
//generates a dataset
let dataset11 = new DataSet()
//fills the dataset with recod values
dataadpter.Fill(dataset11,"tblEmployee")|>ignore
//creates a form
let dataform = new Form(Text="Use OleDbDataAdapter",AutoScaleDimensions=new System.Drawing.SizeF(60.0F, 13.0F),ClientSize=new System.Drawing.Size(300, 200),StartPosition=FormStartPosition.CenterScreen)
//creates an exit button
let exitbutton=new Button(Text="Exit", Location=new System.Drawing.Point(190, 170))  
//creates a gridview control
let datagrid = new DataGridView(Dock=DockStyle.None)
//opens the connection to the datasource
oleconn.Open()
//assign our table
//as a datagrid datasource
datagrid.DataSource <- dataset11.Tables.["tblEmployee"]
//add the controls to our form
dataform.Font<-ffont
dataform.Controls.Add(datagrid)
dataform.Controls.Add(exitbutton)
//when the exit button is clicked
exitbutton.Click.Add(fun exit->
//close the form and dataconnection
dataform.Close()
oleconn.Close())

//executes our application
dataform.Show()
Application.Run(dataform)


5. Click the run icon to execute your application. You should now see an output similar to the following screen shot: