Microsoft KB Archive/114263

= How To VB3: Dynamically Create Excel 5 Charts in OLE 2 Control =

Article ID: 114263

Article Last Modified on 7/15/2004

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APPLIES TO


 * Microsoft Visual Basic 3.0 Professional Edition
 * Microsoft Visual Basic 3.0 Professional Edition
 * Microsoft Excel 5.0 Standard Edition

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This article was previously published under Q114263



SUMMARY
This article demonstrates how to create new Excel 5.0 charts at run-time to be displayed in the Visual Basic OLE 2.0 container control.



MORE INFORMATION
The Visual Basic OLE container control can be used to embed new OLE objects at run time. One of the objects that you can embed is an Excel chart. It is basically a four-step process:


 * 1) To embed a new chart into the OLE control, set the Class property to Excel.Chart or Excel.Chart.5. Both classes (Excel.Chart and Excel.Chart.5) are for Excel charts. But Excel.Chart.5 is version dependent -- it specifies an Excel version 5.0 chart object.
 * 2) Create the object by setting the Action property to OLE_CREATE_EMBED. This embeds a default chart (Chart1) from Excel into the OLE control. The chart (Chart1) is part of a default workbook (Book1) that also contains a default worksheet (Sheet1) to provide data for the chart.
 * 3) Set object variables to reference the Excel objects you need to manipulate the chart through OLE Automation. This will make your code smaller and easier to understand.
 * 4) Call the ChartWizard Method to format the chart.

Setting Object Variables to Reference Excel Objects
The OLE control provides the Object property to allow you to refer to the object you created. For example, the following code creates and embeds a chart into the OLE control and then sets the title: Const OLE_CREATE_EMBED = 0 Ole1.Class = "Excel.Chart.5" Ole1.Action = OLE_CREATE_EMBED Ole1.Object.HasTitle = 1 Ole1.Object.ChartTitle.Caption = "Expenses" You could navigate from the Object property all the time, but it would be cumbersome. To make it easier, you can set object variables to reference the objects you want. Here is a modified version of the previous example with object variables: Const OLE_CREATE_EMBED = 0 Dim objChart as Object Dim objChartTitle as Object Ole1.Class = "Excel.Chart.5" Ole1.Action = OLE_CREATE_EMBED Set objChart = Ole1.Object Set objChartTitle = Ole1.Object.ChartTitle objChart.HasTitle = 1 objChartTitle.Caption = "Expenses" The example shown at the end of this article uses three object variables:


 * One referring to the chart.
 * One referring to the worksheet.
 * One referring to the application object.

Calling the ChartWizard Method to Format a Chart
To format a chart quickly, Excel provides the ChartWizard method. With one call to the ChartWizard method, you can create a chart in one of many predefined formats. The example uses this method, but you could also use direct object manipulation of the chart.

Before you can call the ChartWizard method, the worksheet needs to be filled with the proper data. The example creates random data. Most of the time you will be using more meaningful data that you can manipulate with Excel. In the example, the xlRows orientation is used with 1 row for category labels and one column for series labels. Here is a diagram showing how the data is put into the worksheet:   --- |               | Category 1 Label | Category 2 Label | ---  | Series 1 Label | Data Value       | Data Value       | ---  | Series 2 Label | Data Value       | Data Value       | ---  |                |                  |                  | Once the data (including labels) has been added to the worksheet, you pass the entire range to the ChartWizard method along with the other formatting parameters.

ChartWizard Syntax, Parameters, and Descriptions
SYNTAX:

Object.ChartWizard(Source, Gallery, Format, PlotBy, CategoryLabels, SeriesLabels, HasLegend, Title, CategoryTitle, ValueTitle, ExtraTitle)

Parameter Description
Object         The Chart object. Source         Specifies range that contains source data for the chart. Gallery        Specifies chart type (see constants in example.) Format         Specifies built-in autoformat. PlotBy         Specifies orientation of the data (xlRows or xlColumns.) CategoryLabels The number of rows or columns containing category labels. SeriesLabels   The number of rows or columns containing series labels. HasLegend      Specifies if chart has a legend. Title          The title text of the chart. CategoryTitle  Category axis title text. ValueTitle     Value axis title text. ExtraTitle     Additional axis title text for some charts. The parameters that are most important to the ChartWizard method are:


 * PlotBy
 * CaetgoryLabels
 * SeriesLabels

These parameters either determine how your data is going to be set up, or they are initialized to fit the data you have.

To determine the Gallery and Format parameters, you may want to modify the example. Also, you could record the use of the ChartWizard in Excel and see what parameters are used.

All that is left after calling the ChartWizard method is closing the application and object references.

Step-by-Step Example
 Start a new project in Visual Basic. Form1 is created by default. Add an OLE 2.0 control to Form1, and choose the Cancel button on the Insert Object dialog. Add a command button (Command1) to Form1.  Put the following code in the command button click event. Sub Command1_Click

' Excel chart constants (ODK 1.0 XLCONST.BAS or MsgBox in Excel): Const xlArea = 1 Const xlBar = 2 Const xlColumn = 3 Const xlLine = 4 Const xlPie = 5 Const xlRadar = -4151 Const xlXYScatter = -4169 Const xlCombination = -4111 Const xl3DArea = -4098 Const xl3DBar = -4099 Const xl3DColumn = -4100 Const xl3DLine = -4101 Const xl3DPie = -4102 Const xl3DSurface = -4103 Const xlDoughnut = -4120

' Excel orientation constants: Const xlRows = 1 Const xlColumns = 2

' OLE Constant: Const OLE_CREATE_EMBED = 0 Dim objXL As Object             'Object reference for Excel App Dim objSheet As Object          'Object reference to Excel Worksheet Dim objChart As Object          'Object reference to Excel Chart Dim iRow As Integer             'Index variable for the current Row Dim iCol As Integer             'Index variable for the current Row Dim cRows As Integer            'Number of rows Dim cCols As Integer            'Number of Columns Dim cwSource As String          'Named Range Static cwGallery(15) As Integer 'Array for Chart types Static iGallery As Integer      'Index for Chart type array Dim cwFormat As Integer         'Format of Chart type Dim cwPlotBy As Integer         'How data is taken from Worksheet Dim cwCategoryLabels As Integer 'Rows/Cols with Catagory labels Dim cwSeriesLabels As Integer   'Rows/Cols with Catagory Labels Dim cwHasLegend As Integer      'Display Legend Dim cwTitle As String           'Chart Title Dim cwCategoryTitle As String   'Category Title Dim cwValueTitle As String      'Value Title Dim cwExtraTitle As String      'Extra Title for some Charts

' Fill in array with possible Chart types: cwGallery(1) = xlArea cwGallery(2) = xlBar cwGallery(3) = xlColumn cwGallery(4) = xlLine cwGallery(5) = xlPie cwGallery(6) = xlRadar cwGallery(7) = xlXYScatter cwGallery(8) = xlCombination cwGallery(9) = xl3DArea cwGallery(10) = xl3DBar cwGallery(11) = xl3DColumn cwGallery(12) = xl3DLine cwGallery(13) = xl3DPie cwGallery(14) = xl3DSurface cwGallery(15) = xlDoughnut

' Embed a new Excel 5.0 Chart into the OLE control: Ole1.Class = "Excel.Chart.5" Ole1.Action = OLE_CREATE_EMBED

' Set object references to Chart, Worksheet, and Application objects: Set objChart = Ole1.Object  ' Chart1 default chart

Set objSheet = Ole1.Object.Parent.worksheets(1) ' Sheet1 default data

Set objXL = Ole1.Object.application

' Set the number of columns and rows used for data: cCols = 10 cRows = 3

' Create Series Labels on Worksheet: For iRow = 1 To cRows objSheet.Cells(iRow + 1, 1).Value = "SL" & iRow Next

' Create Category Labels on Worksheet: For iCol = 1 To cCols objSheet.Cells(1, iCol + 1).Value = "CL" & iCol Next

' Create random data on Worksheet: Randomize Timer For iRow = 1 To cRows For iCol = 1 To cCols objSheet.Cells(iRow + 1, iCol + 1).Value = Int(Rnd * 50) + 1 Next iCol Next iRow

' Name the Range containing the previously added data: ' Enter the following two lines as one, single line of code: objSheet.Range(objSheet.Cells(1, 1), objSheet.        Cells(cRows + 1, cCols + 1)).Name = "ChartDataRange"

' Set the ChartWizard parameters: cwSource = "ChartDataRange"      'Name of Named Range iGallery = iGallery Mod 15 + 1   'Iterate through 15 Chart types cwFormat = 1                     'Use default format of Chart Type cwPlotBy = xlRows                'Rows = Series orientation cwCategoryLabels = 1             '1 Row contains Category Labels cwSeriesLabels = 1               '1 Column contains Series Labels cwHasLegend = 1                  'Display the Legend cwTitle = "Embedded Chart"       'Chart Title cwCategoryTitle = "Categories"   'Category Title cwValueTitle = "Values"          'Value Title cwExtraTitle = "Extras"          'Extra Title

' Use the ChartWizard method to fill in the Chart: ' Enter the following three lines as one, single line of code: objChart.ChartWizard cwSource, cwGallery(iGallery), cwFormat, cwPlotBy, cwCategoryLabels, cwSeriesLabels, cwHasLegend, cwTitle, cwCategoryTitle, cwValueTitle, cwExtraTitle ' Shut Down Excel and erase objects: objXL.Quit Set objXL = Nothing Set objChart = Nothing Set objSheet = Nothing

End Sub  Save the project. Run the program, and click the Command1 button. The first chart should be created.</li> Keep clicking the Command1 button to cycle through the fifteen Gallery chart types of Format 1.</li></ol>