ActiveReports objects and controls are completely accessible at run time. The properties of any of the report sections or controls can be modified to produce a dynamic view of the report. The format event allows the properties of report sections and controls to be modified including height, visibility, and other visual properties. The format event is the only event in which the printable area of a section can be modified. Once this event is completed, any changes to the section's height will not be reflected in the report output.

Controls may be added dynamically in the ReportStart event but should not be added dynamically after the ReportStart event is raised as problems may result.

This walkthrough illustrates how to create a report layout at run time based on user input.

This walkthrough is split up into the following activities:

Adding an ActiveReport to a Visual Studio project
Connecting the report to a data source
Adding controls to the Windows Form to contain data
Generating a dataset for the Windows Form
Adding code to create the report layout
Adding code to the Windows Form
Adding code to the report's Detail_Format event
Adding code to the report's ReportStart event
Adding code to the Windows Form's "Generate Report" button Click event
Adding code to the Checked ListBox's SelectedIndexChanged event on the Windows Form
Adding code to the Windows Form_Load event
Viewing the report

To complete the walkthrough, you must have access to the Northwind database.
A copy is located at C:\Program Files\Data Dynamics\ActiveReports for .NET 3.0\Data\NWIND.MDB.

When you have completed this walkthrough, you will have an output that looks similar to the following.

Adding an ActiveReport to your project

To add an ActiveReport to your project

From the Project menu, select Add New Item.
Select ActiveReports 3.0 File and rename the file rptFieldsRT.
Click Open.

Connecting the report to a data source

To connect the report to a data source

Click on the gray report DataSource icon in the Detail section to open the report DataSource dialog.
Click on Build.
Select "Microsoft Jet 4.0 OLE DB Provider" and click Next.
Click the ellipsis button to browse for the access path to the Northwind database. Click Open once you have selected the appropriate access path.
Click OK to continue.
In the Query field, type "Select * from products".
Click OK to return to the report design surface.

Adding controls to the Windows Form to contain data

To add controls to the form

Control	Location	Dock Property	Name	Text
Panel	Windows Form	Left	Panel1
Label	Panel1	Top	lblSelectFields	Select Fields for Your Report
Checked ListBox	Panel1	Fill	clbFields
Button	Panel1	Bottom	btnGenRep	Generate Report
CheckBox	Panel1	Bottom	chkGroup	Group By Category ID
Viewer	Windows Form	Fill	Viewer1

Generating a dataset for the Windows Form

To generate the dataset

From the Project menu, select Add New Item.
Select DataSet, rename the file to NWINDDataSet.xsd and click the Add button.
Open the Server Explorer by clicking its link in the DataSet designer.
In the Server Explorer, expand the node for your local copy of the Northwind database and drag the Products table onto the DataSet designer. If you do not see a copy of the Northwind database, click the "Connect to Database" icon and follow the prompts.
In the design view of your Windows form, expand the Data section of the Visual Studio Toolbox and double-click DataSet to open the Add Dataset dialog.
Under Typed dataset, select <project name>.NWINDDataSet and click OK to make the dataset available to your Windows form.

Adding code to create the report layout

To add code to create the report layout

Right-click on rptFieldsRT and select "View Code." Insert the following code within the class declaration of the report.

'Visual Basic
Private m_arrayFields As ArrayList
Private m_useGroups As Boolean
Public WriteOnly Property FieldsList() As ArrayList
   Set(ByVal Value As ArrayList)
       m_arrayFields = Value
   End Set
End Property
Public WriteOnly Property UseGroups() As Boolean
   Set(ByVal Value As Boolean)
       m_useGroups = False
       m_useGroups = Value
   End Set
End Property
Private m_defaultHeight As Single = 0.2F
Private m_defaultWidth As Single = 4.0F
Private m_currentY As Single = 0.0F
Private Sub constructReport()
   Try
      Me.Detail1.CanGrow = True
      Me.Detail1.CanShrink = True
      Me.Detail1.KeepTogether = True
      If m_useGroups = True Then
          Me.Sections.InsertGroupHF()
          CType(Me.Sections("GroupHeader1"), GroupHeader). _
             DataField = "CategoryID"
          Me.Sections("GroupHeader1").BackColor = System.Drawing. _
             Color.Gray
          Me.Sections("GroupHeader1").CanGrow = True
          Me.Sections("GroupHeader1").CanShrink = True
          CType(Me.Sections("GroupHeader1"), GroupHeader).RepeatStyle _
             = RepeatStyle.OnPageIncludeNoDetail
          Dim txt As New TextBox
          txt.DataField = "CategoryID"
          txt.Location = New System.Drawing.PointF(0.0F, 0)
          txt.Width = 2.0F
          txt.Height = 0.3F
          txt.Style = "font-weight: bold; font-size: 16pt"
          Me.Sections("GroupHeader1").Controls.Add(txt)
      End If
      Dim i As Integer
      For i = 0 To m_arrayFields.Count - 1
          If m_arrayFields(i).ToString <> "CategoryID" Then
              Dim lbl As New Label
              lbl.Text = m_arrayFields(i) + ":"
              lbl.Location() = New System.Drawing.PointF _
                (0.0F, m_currentY)
              lbl.Width = 0.9F
              lbl.Height = m_defaultHeight
              Me.Detail1.Controls.Add(lbl)
              Dim txt As New TextBox
              txt.DataField = m_arrayFields(i)
              txt.Location = New System.Drawing.PointF _
                (1.0F, m_currentY)
              txt.Width = m_defaultWidth
              txt.Height = m_defaultHeight
              Me.Detail1.Controls.Add(txt)
              If m_arrayFields(i) = "UnitPrice" Then
                 txt.OutputFormat = "$#.00"
              End If
                 m_currentY = m_currentY + m_defaultHeight
              End If
       Next
   Catch ex As Exception
       System.Windows.Forms.MessageBox.Show _
         ("Error in Report-constructReport: " + ex.Message, "Project Error", _
         System.Windows.Forms.MessageBoxButtons.OK, _
          System.Windows.Forms.MessageBoxIcon.Error)
   End Try
End Sub

//C#
private ArrayList m_arrayFields;
public ArrayList FieldsList
{
   set{m_arrayFields = value;}
}
private bool m_useGroups = false;
public bool UseGroups
{
   set{m_useGroups = value;}
}
float m_defaultHeight = .2f;
float m_defaultWidth = 4f;
float m_currentY = 0f;
private void constructReport()
{
   try
   {
      this.detail.CanGrow = true;
      this.detail.CanShrink = true;
      this.detail.KeepTogether = true;
      if(m_useGroups)
      {
	this.Sections.InsertGroupHF();
	((GroupHeader)this.Sections["GroupHeader1"]).DataField =
	   "CategoryID";
	this.Sections["GroupHeader1"].BackColor = System.Drawing
	   .Color.Gray;
	this.Sections["GroupHeader1"].CanGrow = true;
	this.Sections["GroupHeader1"].CanShrink = true;
	((GroupHeader)this.Sections["GroupHeader1"]).RepeatStyle =
	   RepeatStyle.OnPageIncludeNoDetail;
	this.Sections["GroupFooter1"].Height = 0;
	TextBox txt = new TextBox();
	txt.DataField = "CategoryID";
	txt.Location = new System.Drawing.PointF(0f,0);
	txt.Width =2f;
	txt.Height = .3f;
	txt.Style = "font-weight: bold; font-size: 16pt;";
	this.Sections["GroupHeader1"].Controls.Add(txt);
      }
      for(int i=0;i<m_arrayFields.Count;i++)
      {
	if(!m_useGroups || (m_useGroups && m_arrayFields[i]
	   .ToString() != "CategoryID"))
	{
	   Label lbl = new Label();
	   lbl.Text = m_arrayFields[i].ToString() + ":";
	   lbl.Location = new System.Drawing.PointF
	      (0f,m_currentY);
	   lbl.Width =.9f;
	   lbl.Height = m_defaultHeight;
	   this.detail.Controls.Add(lbl);
	   TextBox txt = new TextBox();
	   txt.DataField = m_arrayFields[i].ToString();
	   txt.Location = new System.Drawing.PointF
	   (1f,m_currentY);
	   txt.Width = m_defaultWidth;
	   txt.Height = m_defaultHeight;
	   this.detail.Controls.Add(txt);
	   m_currentY = m_currentY + m_defaultHeight;
	}
      }
   }
   catch(Exception ex)
   {
      System.Windows.Forms.MessageBox.Show("Error in Report-constructReport: " 
	+ ex.Message,"Project Error",System.Windows.Forms
	.MessageBoxButtons.OK,System.Windows.Forms.MessageBoxIcon.Error);
   }
}

Adding code to the Windows Form

To add code to the form

Right-click on the Windows Form and select "View Code." Insert the following code within the class declaration of the Form (after the Main() method for C# 2003).

'Visual Basic
Dim i As Integer
Dim c As Integer
Dim m_arrayField As New ArrayList()
Private Sub fillCheckBox()
   For i = 0 To Me.DataSet11.Tables.Count - 1
      For c = 0 To Me.DataSet11.Tables(i).Columns.Count - 1
	Me.clbFields.Items.Add(Me.DataSet11.Tables(i).Columns(c).ColumnName)
      Next
   Next
End Sub
Private Sub launchReport()
   Dim rpt As New rptFieldsRT()
      Try
	   rpt.FieldsList = m_arrayField
	   rpt.UseGroups = chkGroup.Checked
	   rpt.DataSource = this.DataSet11.Products.TableName
	   Viewer1.Document = rpt.Document
	   rpt.Run()
	Catch ex As Exception
	   System.Windows.Forms.MessageBox.Show(Me, "Error in launchReport: " _
		+ ex.Message, "Project Error", MessageBoxButtons.OK, _
		MessageBoxIcon.Error)
      End Try
End Sub

//C#
//Place this code after the Main() method in Visual Studio for .NET 2003
ArrayList m_arrayField = new ArrayList();
private void fillCheckBox()
{
   for(int i = 0; i < this.dataSet11.Tables.Count; i++)
   {
      for(int c = 0; c < this.dataSet11.Tables[i].Columns.Count; c++)
      {
	this.clbFields.Items.Add(this.dataSet11.Tables[i].Columns[c]
	   .ColumnName);
      }
   }
}
private void launchReport()
{
   try
   {
      rptFieldsRT rpt = new rptFieldsRT();
      rpt.FieldsList = m_arrayField;
      rpt.UseGroups = chkGroup.Checked;
      rpt.DataSource = this.dataSet11.Products.TableName;
      this.viewer1.Document = rpt.Document;
      rpt.Run();
   }
   catch(Exception ex)
   {
      MessageBox.Show(this,"Error in launchReport: " + ex.Message,"Project
	Error",MessageBoxButtons.OK,MessageBoxIcon.Error);
   }
}

Adding code to the Detail_Format event

To write the code in Visual Basic or C#

Double-click in the detail section of rptFields. This creates an event-handling method for rptFieldsRT's Detail_Format event.

The following example shows what the code for the method looks like.

'Visual Basic
Dim m_count As Integer
Private Sub Detail1_Format(ByVal sender As Object, ByVal e As System.EventArgs) _
   Handles Detail1.Format
   If m_count Mod 2 = 0 Then
     Me.Detail1.BackColor = System.Drawing.Color.SlateGray
   Else
     Me.Detail1.BackColor = System.Drawing.Color.Gainsboro
   End If
   m_count = m_count + 1
End Sub

//C#
int m_count;
private void detail_Format(object sender, System.EventArgs eArgs)
{
   if(m_count % 2 == 0)
   {
     this.detail.BackColor = System.Drawing.Color.SlateGray;
   }
   else
   {
     this.detail.BackColor = System.Drawing.Color.Gainsboro;
   }
   m_count++;
}

Adding code to the ReportStart event

To write the code in Visual Basic or C#

Double-click in the gray area below rptFieldsRT to create an event-handling method for rptFieldsRT's ReportStart event. Add the following code to call the ConstructReport() method.

The following example shows what the code for the method looks like.

'Visual Basic
Private Sub rptFieldsRT_ReportStart(ByVal sender As Object, ByVal e As _
   System.EventArgs) Handles MyBase.ReportStart
constructReport()
End Sub

//C#
private void rptFieldsRT_ReportStart(object sender, System.EventArgs eArgs)
{
   constructReport();
}

Adding code for btnGenRep's Click event

To write the code in Visual Basic or C#

Double-click btnGenRep to create an event-handling method for btnGenRep's Click event. Add the following code to the btnGenRep_Click event.

The following example shows what the code for the method looks like.

'Visual Basic
Private Sub btnGenRep_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) _
   Handles btnGenRep.Click
   Me.m_arrayField.Clear()
   For i = 0 To Me.clbFields.CheckedItems.Count - 1
     m_arrayField.Add(Me.clbFields.CheckedItems(i).ToString)
   Next
   launchReport()
End Sub

//C#
ArrayList m_arrayField = new ArrayList();
private void btnGenRep_Click(object sender, System.EventArgs e)
{
   this.m_arrayField.Clear();
   for(int i = 0; i < this.clbFields.CheckedItems.Count; i++)
   {
     m_arrayField.Add(this.clbFields.CheckedItems[i].ToString());
   }
   launchReport();
}

Adding code to the clbFields_SelectedIndexChanged event

To write the code in Visual Basic

Right-click in any section of the Windows Form, and click on View Code to display the code view for the Windows Form. At the top left of the code view for the form, click the drop-down arrow and select clbFields. At the top right of the code window, click the drop-down arrow and select SelectedIndexChanged. This creates an event-handling method for the clbFields_SelectedIndexChanged event.

To write the code in C#

Click clbFieds to select it. Click on the events icon in the Properties window to display available events and double-click SelectedIndexChanged. This creates an event-handling method for the clbFields_SelectedIndexChanged event.

The following example shows what the code for the method looks like.

'Visual Basic
Private Sub clbFields_SelectedIndexChanged(ByVal sender As Object, ByVal e _
   As System.EventArgs) Handles CheckedListBox1.SelectedIndexChanged
   If Me.clbFields.CheckedItems.Count < 0 Then
     Me.btnGenRep.Enabled = False
   Else
     Me.btnGenRep.Enabled = True
   End If
 End Sub
 
//C#
private void clbFields_SelectedIndexChanged(object sender, System.EventArgs e)
{
   if(this.clbFields.CheckedItems.Count>0)
   {
      this.btnGenRep.Enabled = true;
   }
   else
   {
      this.btnGenRep.Enabled = false;
   }
}

Adding code to the Windows Form_Load event

To write the code for the viewer in Visual Basic or C#

Double-click the title bar of the form. This creates an event-handling method for the Windows Form_Load event. Add code to the handler to:

Call the fillCheckBox() method to populate clbFields with field values

The following example shows what the code for the method looks like.

'Visual Basic
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) _
   Handles MyBase.Load
   Try
     fillCheckBox()
    Catch ex As Exception
    System.Windows.Forms.MessageBox.Show(Me, "Error in Form1_Load: " + ex _
	.Message, "Project Error", MessageBoxButtons.OK, MessageBoxIcon.Error)
   End Try
End Sub

//C#
private void Form1_Load(object sender, System.EventArgs e)
{ 
  try
  {
     fillCheckBox();
  }
  catch(Exception ex)
  {
     MessageBox.Show(this,"Error in Form1_Load: " + ex.Message,"Project Error", +
     MessageBoxButtons.OK,MessageBoxIcon.Error);
  }
}

Viewing the report

To view the report

Press F5 to run the project.
Select fields in the Checked list box.
Click the Generate Report button.

You can quickly view your report at design time by clicking the Preview tab at the bottom of the designer.

ActiveReports for .NET 3 Online Help	Request technical support
Walkthrough: Creating and Modifying Report Layouts at Run Time
See Also

Adding an ActiveReport to your project

Connecting the report to a data source

Adding controls to the Windows Form to contain data

Generating a dataset for the Windows Form

Adding code to create the report layout

Adding code to the Windows Form

Adding code to the Detail_Format event

Adding code to the ReportStart event

Adding code for btnGenRep's Click event

Adding code to the clbFields_SelectedIndexChanged event

Adding code to the Windows Form_Load event

Viewing the report

See Also