Trouble viewing this newsletter? Click here to read it online
Dundas Software Ltd. Brought to you by!

Editor's Note: December!

Along with a great number of holidays, December has brought along presents in the form of a more useful Dundas Support Site; articles can now be rated and "Top Articles" are ordered based on this rating. Support Site users now have a voice in determining the popularity and visibility of articles, which I hope translates into a better support experience for everyone. I should also mention that December marks the return of the Dundas Win/Web Combo sale. Like Christmas, it only comes once a year.

November's newsletter mentioned a map resource article which existed on the Dundas Support Site. The article in question has been moved to its new home: its own page on This page will be updated on a regular basis to provide an always up-to-date source for shape file resources. If you still have a direct link to the old article then you will notice it is still visible and will remain so in the interim. However, do note everything within it is already in the new page.

Terrence Sheflin

In this Issue: December 19, 2006

Send your feedback


AJAX Based Series Selection (Add-On)

The AJAX Based Series Selection Add-On lets you highlight a series by placing the mouse over the legend in an ASP.NET application. The highlighted series will become the prominent series through a color change; the unselected series are sent to the background through an applied semitransparent color. This functionality allows a user to quickly focus on the desired data by sifting through a large number of series.

Full control over the color of the highlighted series and the alpha value used for the background series is available in the add-on class through public functions. Typical usage of this add-on class is as simple as the following line of code: AJAXSelection AJAX = new AJAXSelection(Chart1, true);. The constructor of this class takes two parameters: the Chart object to be used and a Boolean value specifying whether or not the add-on should generate all the images it uses immediately. If the Boolean parameter is set to false, then a call to MakeImages must be made before the add-on will work.

The AJAX Based Series Selection Add-On will work with both Professional and Enterprise versions of Dundas Chart. However, it should be noted that since this add-on makes use of the Callback functionality built into .NET 2.0, it is only available for Visual Studio 2005.

Tips n' Tricks Chart | Gauge | Map

General Tips

Dundas for Windows Presentation Foundation (WPF)
Dundas Software has begun ground-up development of visualization controls for the WPF platform. Because the WPF environment is substantially different from its predecessors, simply porting controls to the new platform does not make sense. The ease of use associated with current Dundas controls can be expected in the new versions of our controls, as well as many enhancements based on the new functionality available in the .NET 3.0 framework. For example, data-binding in WPF is completed using only one line of code: <Dundas:ChartControl DataSource="{StaticResource mySource}" Name="Chart" />.
read more »

Dynamic Assembly Loading using Reflection
Assemblies can be loaded at run-time through the System.Reflection namespace. While assembly calls are more complicated when using this method, it has a few unique advantages. One situation in which using Reflection to load an assembly proves advantageous is where an application must be built without having references to the assembly itself. This is useful when you have two versions of your product: one which uses the Dundas Software assembly and one which does not. In this case, using Reflection results in neither version needing a direct reference to the Dundas Software assembly.

Using Reflection to load assemblies also lets you avoid dealing with directives at the top of ASPX pages (in ASP.NET) and references within the Web.Config file. Furthermore, using Reflection gives the freedom to place assemblies anywhere on the hard drive and avoid registering them into the GAC.
read more »

Add a Logo to Your Chart as a Semitransparent Watermark
The evaluation version of Dundas Chart uses a semitransparent watermark in order to notify users that it is an evaluation copy. This functionality can now be reproduced by any company through use of the method provided in the full article. The method, CreateWaterMark, is a method which takes any standard image, applies a semitransparent or alpha blend to it and then draws the modified image in the center of the chart area. CreateWaterMark also allows you to set a completely transparent color and specify the size of the watermark.
read more »

Chart for .NET - OLAP Services

Drill-Through Using Grid
As with the Chart, the Grid can be manipulated through use of the OLAP Manager. OLAP Manager acts as the central processor of our OLAP Services product; most functions contained within the OLAP Manager can be applied to both the Chart and the Grid. The distributed sample set provides an example of how to drill-through on the Chart and is a good reference for building a drill-through Grid, as the process for creating a drill-through using the Grid is similar to using the Chart: Use Callbacks to handle the click of an item, determine which item was clicked and change the information displayed.
read more »

Adding Data to Dundas Gauge for Reporting Services
There are several ways to specify data for Gauge for Reporting Services:

  • Use the Data Tab of the Gauge Wizard when creating your main Gauge element and specify a dataset as well as an expression for the control's pointer, state and numeric indicator values. Note that this tab lets you set the value of all gauge elements in the control that take a value.
  • If the main Gauge is an indicator, use the General Tab of the Gauge Designer to specify its value.
  • If the main Gauge is a circular or linear gauge, use the Pointers Tab to set the value of the pointers.
  • Use the Report Designer and drag and drop a data field from the Datasets window onto the Value Fields landing zone. These drop zones will already be populated with fields if set using a dialog.

One important thing to note about data-binding is that using grouping in your SQL statement allows the Gauge to see all columns available rather than just the first column. This is especially important when statistical formulas are used, as they only have an effect if applied to multiple values.
read more »

Displaying Dundas Chart as Symbols On Your Map
Dundas Chart can be placed on your Map as a symbol, legend icon, or an image within Map's Images collection. To implement a solution which uses Dundas Chart within Map, first put Dundas Chart in BinaryStreaming mode. Then, within an element in Map, reference the full URL path which leads to the ASPX page containing the Chart. Though the example application within the article uses static images for the Chart legend icons, dynamic images can be used as well by making a second Chart ASPX page.
read more »

Map for Reporting Services

Adding Symbols From a Database in Dundas Map for Reporting Services
In Dundas Map for Reporting Services, shapes, paths and symbols can be loaded into Dundas Map by right-clicking the Map and choosing "Import Shapefiles" or by adding symbols in the Map control's Symbols collection. The configurable data fields within the report designer allow you to bind the database to the loaded shapes, paths or symbols. In addition to the report designer, symbols can be added to the map directly from the database using Dundas Map's code editor. The steps for adding symbols through the code editor are explained in the full article.
read more »

Dundas Q & A Chart | Gauge | Map

Chart for .NET

Q. Can I use one data reader object to create more than one series?
A. Yes, you can use one data reader object to create more than one series if you use Microsoft SQL Server because Microsoft SQL Server supports batch queries. SqlDataReader class' NextResult method is used to process multiple results, which are generated by executing batch Transact-SQL statements. By default, the data reader is positioned on the first result.
read more »

Chart for .NET - OLAP Services

Q. How can I restrict access to certain data in OLAP Services?
A. Data can be restricted through both SQL Analysis Services and Dundas OLAP Services. In SQL Analysis Services, roles and user access rights are used to restrict data to users. In Dundas OLAP Services, the Visible property of individual dimensions, hierarchies, levels and members provides control over what each user can and cannot see. An example of how to use Dundas OLAP Services to restrict access rights is contained within the full article.
read more »

Gauge for .NET

Q. Why are temporary images created in my root directory by Dundas Gauge for ASP.NET?
A. Dundas Gauge for ASP.NET works by generating images which are viewed in the client's browser. When an ASPX page that has a Gauge control on it is rendered into HTML and sent to the client, it contains an IMG tag that refers to an image on the server. These images need to be generated by the server for the client's browser to retrieve them.

By default, Gauge uses a round robin method of image file management with a maximum of 300 files set in the ImageUrl property. Once 300 files are written, the old files are overwritten. For more details, refer to the Managing Image Files article in our documentation.

Gauge for Reporting Services

Q. I'm having troubles using Dundas Gauge for Reporting Services on a 64-bit machine directly after the install. How can I remedy this?
A. Normally the installer will copy RSGaugeInstaller.exe and run it at the end of the install process. However, if you are using a 64-bit machine, the installer may fail to run this file. In this case it is possible to run the file yourself in order to complete the install process. To run the RSGaugeInstaller.exe file manually, navigate to C:\Program Files (x86)\Dundas Software\Gauges\Reporting Services\Tools (default install location). If this does not solve the issue, please refer to the full article for manual installation steps.
read more »

Map for .NET

Q. How do I show only some elements in the legend or color swatch panel?
A. When the ShowInLegend or ShowInColorSwatch property is set on a shape, path, symbol or group rule the elements and their colors generated by the rule are automatically added to the legend's Items collection or to the color swatch panel. If you have a lot of elements and the rule's field property is set to "(Name)", then this may cause the legend or color swatch to become unreadable due to the high number of items.

To display only some items in the legend, set the Category property of your rule and your elements. Setting this property in all the elements which are to be visible to the same string of text as the rule, such as "ShowInLegend", will cause the items to show up in the legend and no others. This is done easiest at design time, but can also be done in the code behind at run time.
read more »

Map for Reporting Services

Q. Why aren't my data fields being displayed or added in Dundas Map for Reporting Services?
A. When adding "Displayed Fields" or "Data Fields" to Dundas Map for Reporting Services, there are a few things to check to ensure they will display: Setting up the fields, Matching to the binding field, Data appearance and Numeric field types. These items are each addressed in the full article and, if followed, will result in the data fields being added properly.
read more »