Reusing .NET Framework 4+ ReportLibrary Reports in .NET
Environment
| Product Version | 13.0.19.116+ |
| Product | Progress® Telerik® Reporting |
Visual Studio Report Designer for .NET Preview
Starting with the Telerik Reporting 2026 Q3 October release (20.2.26.1007), the Visual Studio Report Designer for .NET (VSRD.NET) is available as a preview. You can now migrate your existing C# or VB coded reports to a supported SDK-style .NET report library and continue editing and previewing them directly in Visual Studio, retaining their custom code.
See Getting Started with the Visual Studio Report Designer for .NET for prerequisites and setup. The preview requires Visual Studio 2026 version 18.10 or later and a report project targetingnet8.0-windowsor later withUseWindowsForms=true.
Description
Existing .NET Framework report libraries must be migrated to a compatible .NET or .NET Standard class library, or converted to declarative report definitions, for use in a .NET application.
The .NET Framework Visual Studio Report Designer requires a .NET Framework report project. Before the VSRD.NET preview, retaining Visual Studio design-time support for migrated reports required a linked .NET Framework project. For supported SDK-style .NET projects, the preview removes that requirement. It does not add direct design-time support for .NET Standard projects or older .NET Core targets.
Solution
There are two approaches to resolve the problem depending on the amount of custom code used in the report definitions.
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If the report classes do not contain custom code (i.e. handlers for events like NeedDataSource, ItemDataBound, etc.) or this code can be substituted with conditional formatting and bindings in the report definition, it is recommended to use the Standalone Report Designer to import them into a set of
.TRDP/.TRDXreports, as explained in the article on importing reports created with the VS Report Designer.If the report uses class library assemblies that contain user functions or provide data for ObjectDataSource instances, you may use the .NET version of the Standalone Designer. For the .NET Framework version of the designer, their projects need to be migrated to .NET Standard so that it may be able to load the assemblies and provide design-time support for them.
The produced
.TRDP/.TRDXdefinitions can be used through a UriReportSource in a .NET Core application. -
If the custom code in the report definitions must be retained, copy all report files (
.cs,.designer.cs, and.resx, or their VB equivalents) to a new SDK-style .NET report library. To edit the migrated reports directly in Visual Studio with the VSRD.NET preview, configure the report project with the required target framework, project settings, and matchingTelerik.ReportingandTelerik.Reporting.VSDesignerpackage versions. Restore the packages and build the project, then right-click the report's main.csor.vbfile in Solution Explorer and select View Designer.Once the project compiles, the report classes it contains can be used through a TypeReportSource or InstanceReportSource in a compatible .NET application. Ensure that the consuming application's target framework is compatible with the report library's Windows-specific target framework.
For older Telerik Reporting releases or environments that do not meet the preview prerequisites, you can still link the C# report files to a .NET Standard or .NET Core library and edit them through a .NET Framework project, as described in How to use Visual Studio Report Designer to edit CS Reports in .NET Projects.
Declarative .TRDP or .TRDX report definitions remain recommended when custom report code is not required. Converting to declarative reports is no longer necessary solely to retain design-time support after migrating to a supported SDK-style .NET project.