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.

 

Note: Controls are added dynamically in the ReportStart event. Controls added dynamically after the ReportStart event cause problems.

This walkthrough illustrates how to create a report layout at run time based on user input using Visual Studio 2003.

 

This walkthrough is split up into the following activities:

• Creating a user interface
• • Adding controls to a Windows Form
  • Generating a dataset for the Windows Form
• Adding an ActiveReport to the project
• • Connecting the report to a data source
  • Creating an array list and adding controls to the report at run time
  • Adding code to the ReportStart event to call the constructReport method
  • Adding code to the Detail Format event to alternate colors in the report
• Adding code to the Windows Form
• • Creating a method to fill the check list box with field values
  • Adding code to the Form Load event to call the fillCheckBox method
  • Adding code to retrieve user input from the check list box
  • Creating a method to launch the report
  • Adding code to the button Click event to populate the array list and pass it to the report
• Selecting fields and viewing the report   

To complete the walkthrough, you must have access to the NorthWind database (NWind.mdb).

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

CREATING A USER INTERFACE

Adding controls to a Windows Form

To add controls to the form

• Create a new Visual Studio Windows Application project and resize Form1 to the size you prefer.
• Add the controls in the table below to Form1 and set the properties as indicated:

   

  Control	Dock Property	Name	Text	Misc. Details
  Panel	Left	pnlFields		Width: 200
  Label	Top	lblSelectFields	Select Fields for Your Report	Container: pnlFields
  Checked ListBox	Fill	clbFields		Container: pnlFields
  Button	Bottom	btnGenRpt	Generate Report	Container: pnlFields
  Viewer (Drag onto right side of form.)	Fill	Viewer1		Container: Windows Form

Generating a dataset for the Windows Form

To generate a dataset for the Windows Form

1. On the Data toolbox, double-click OleDbDataAdapter.
2. This adds the adapter to the Windows Form and opens the Data Adapter Configuration Wizard.
3. Follow the instructions to choose the data connection, select the data provider, select the database and enter the SQL statement, "SELECT CategoryID, Discontinued, ProductID, ProductName, QuantityPerUnit, ReorderLevel, SupplierID, UnitPrice, UnitsInStock, UnitsOnOrder FROM Products" (For help with this, see "Connecting the report to a data source" below.)
4. Click "Finish" to return to the Windows Form.
5. From the Visual Studio Data menu, select Generate Dataset...
6. This opens the Generate Dataset dialog.
7. Select New and select the Products table check box.
8. Check "Add this dataset to the designer" and click OK.

ADDING AN ACTIVEREPORT TO THE PROJECT

To add an ActiveReport to your project

1. From the Project menu, select Add New Item..., select ActiveReports File, and name the file rptFieldsRT.
2. Click Open.

Connecting the report to a data source

To connect the report to a data source

1. Click on the yellow report DataSource icon in the Detail section to open the Report Data Source dialog.
2. Click the Build... button.
3. Select "Microsoft Jet 4.0 OLE DB Provider" and click the Next >> button.
4. Click the ellipsis button to navigate to Nwind.mdb and click the Open button.
5. Click OK to continue.
6. In theQuery field, type "Select * from products".
7. Click OK to return to the report design surface.

Creating an array list and adding controls to the report at run time

To create an array list and add controls at run time

In the code view of rptFieldsRT, insert the following code beneath "ActiveReports Designer generated code."

' Visual Basic
Private m_arrayFields As ArrayList
Public WriteOnly Property FieldsList() As ArrayList
        Set(ByVal Value As ArrayList)
                m_arrayFields = 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.Detail.CanGrow = True
                Me.Detail.CanShrink = True
                Me.Detail.KeepTogether = True
                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.Detail.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.Detail.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 System.Collections.ArrayList m_arrayFields;
public System.Collections.ArrayList FieldsList
{
        set{m_arrayFields = 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;
                for(int i=0;i<m_arrayFields.Count;i++)
                {
                        if(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 ReportStart event to call the constructReport method

To write the code in Visual Basic

• At the top left of the code view for rptFieldsRT, click the drop-down arrow and select (rptFieldsRT Events). At the top right of the code window, click the drop-down arrow and select ReportStart. This creates an event-handling method for rptFieldsRT's ReportStart event.

To write the code in C#

• In the design view of rptFieldsRT, click in the gray area below the report to select it. Click on the events icon in the Properties window to display available events for the report. Double-click ReportStart. This creates an event-handling method for rptFieldsRT's ReportStart event.

  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 to the Detail Format event to alternate colors in the report

To write the code in Visual Basic

• At the top left of the code view for rptFieldsRT, click the drop-down arrow and select Detail. At the top right of the code window, click the drop-down arrow and select Format. This creates an event-handling method for rptFieldsRT's Detail_Format event.

To write the code in C#

• In the design view of rptFieldsRT, click in the Detail section to select the section. Click on the events icon in the Properties window to display available events for the section. Double-click Format. 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 Detail_Format(ByVal sender As Object, ByVal e As System.EventArgs) _
   Handles Detail.Format
         If m_count Mod 2 = 0 Then
             Me.Detail.BackColor = System.Drawing.Color.SlateGray
          Else
                  Me.Detail.BackColor = System.Drawing.Color.DarkSeaGreen
       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.DarkSeaGreen;
    }
     m_count++;
  }
  

ADDING CODE TO THE WINDOWS FORM

Creating a method to fill the check list box with field values

To create a method to fill the check list box

• In the code view of Form1, insert the following code in the Form1 Class statement. 

  ' Visual Basic
  Dim i As Integer
  Dim c As Integer
  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
  

  //C#
  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);
                  }
          }
  }
  

Adding code to the Form Load event to call the fillCheckBox method

To write the code in Visual Basic

• At the top left of the code view for Form1, click the drop-down arrow and select (Form1 Events). At the top right of the code window, click the drop-down arrow and select Load. This creates an event-handling method for the Form1_Load event. Add code to the handler to call the fillCheckBox method.

To write the code in C#

• In the design view of Form1, click the top edge of the form to select it. Click the events icon in the Properties window to display available events for Form1. Double-click Load. This creates an event-handling method for the Form1_Load event. Add code to the handler to call the fillCheckBox method.

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

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

Adding code to retrieve user input from the check list box

To write the code in Visual Basic

• 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#

• In the design view of Form1, click clbFields to select it. Click on the events icon in the Properties window to display available events for clbFields. 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 clbFields.SelectedIndexChanged
          If Me.clbFields.CheckedItems.Count = 0 Then
              Me.btnGenRpt.Enabled = False
          Else
              Me.btnGenRpt.Enabled = True
          End If
   End Sub
  

  //C#
  private void clbFields_SelectedIndexChanged(object sender, System.EventArgs e)
  {
      if(this.clbFields.CheckedItems.Count>0)
    {
             this.btnGenRpt.Enabled = true;
        }
     else
          {
             this.btnGenRpt.Enabled = false;
       }
  }
  

Creating a method to launch the report

To create a method to launch the report

• In the code view of Form1, insert the following code after the SelectedIndexChanged event. 

  ' Visual Basic
  Dim m_arrayField As New ArrayList
  Private Sub launchReport()
          Dim rpt As New rptFieldsRT()
          Try
                  rpt.FieldsList = m_arrayField
                  rpt.DataMember = Me.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#
  System.Collections.ArrayList m_arrayField = new System.Collections.ArrayList();
  private void launchReport()
  {
          try
          {
                  rptFieldsRT rpt = new rptFieldsRT();
                  rpt.FieldsList = m_arrayField;
                  rpt.DataMember = 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 for the button Click event to populate the array list and pass it to the report

To write the code in Visual Basic

• In the design view of Form1, double-click btnGenRpt. This creates an event-handling method for the btnGenRpt Click event. Add the following code to the btnGenRpt_Click event.

To write the code in C#

• In the design view of Form1, double-click btnGenRpt to create an event-handling method for the btnGenRp Click event. Add the following code to the btnGenRpt_Click event.

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

' Visual Basic
Private Sub btnGenRpt_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) _
      Handles btnGenRpt.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#
private void btnGenRpt_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();
}

Selecting fields and viewing the report

To select fields and view the report

• Run the project.
• Select fields in the check list box.
• Click the Generate Report button.

Samples | Walkthroughs

 

 

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