# Action NavigateToReport does not work after updating the Connection String dynamically in a Custom Report Resolver

## Environment

<table>
	<tr>
		<td>Product</td>
		<td>Progress® Telerik® Reporting</td>
	</tr>
</table>

## Description

Sometimes it is necessary to change the connection string dynamically, in the code. The approach described in  [Changing the connection string dynamically according to runtime data](https://www.telerik.com/products/reporting/documentation/knowledge-base/changing-the-connection-string-dynamically-according-to-runtime-data) KB article is suitable for Desktop Viewers.
It can be applied also for the Html5 Web Viewers **with some modifications**. The connection string should be changed in the `Resolve()` method of the Custom Report Resolver.

When there is a `NavigateToReport` Action set for any report item, the action will not work after updating the connection string.

## Solution

The above KB article drills through the entire report to modify the connection string of all its *Items*, *Parameters* and *Actions*. The code from the KB searches for *NavigateToReport* Actions, and replaces recursively the connection string also in Action *ReportSources*. That is where the problem occurs. You should **remove** the corresponding code that **drills through the Actions**, as it is excessive in the case of *Html5 Report Viewer / REST Service*. The *REST Service* will automatically resolve the *ReportSource* of the *NavigateToReport* Action using the Custom Report Resolver, hence its connection string will be automatically modified and it is not necessary to drill through actions in the main report.

The following code is appropriate for applications using Telerik Reporting REST Service:

```CSharp
class ReportConnectionStringManager
{
	readonly string connectionString;
	
	public ReportConnectionStringManager(string connectionString)
	{
		this.connectionString = connectionString;
	}
	
	public ReportSource UpdateReportSource(ReportSource sourceReportSource)
	{
		if (sourceReportSource is UriReportSource)
		{
			var uriReportSource = (UriReportSource)sourceReportSource;
			// unpackage TRDP report
			var reportInstance = UnpackageReport(uriReportSource);
			// or deserialize TRDX report(legacy format)
			// var reportInstance = DeserializeReport(uriReportSource);
			ValidateReportSource(uriReportSource.Uri);
			this.SetConnectionString(reportInstance);
			return CreateInstanceReportSource(reportInstance, uriReportSource);
		}
	
		if (sourceReportSource is XmlReportSource)
		{
			var xml = (XmlReportSource)sourceReportSource;
			ValidateReportSource(xml.Xml);
			var reportInstance = this.DeserializeReport(xml);
			this.SetConnectionString(reportInstance);
			return CreateInstanceReportSource(reportInstance, xml);
		}
	
		if (sourceReportSource is InstanceReportSource)
		{
			var instanceReportSource = (InstanceReportSource)sourceReportSource;
			this.SetConnectionString((ReportItemBase)instanceReportSource.ReportDocument);
			return instanceReportSource;
		}
	
		if (sourceReportSource is TypeReportSource)
		{
			var typeReportSource = (TypeReportSource)sourceReportSource;
			var typeName = typeReportSource.TypeName;
			ValidateReportSource(typeName);
			var reportType = Type.GetType(typeName);
			var reportInstance = (Report)Activator.CreateInstance(reportType);
			this.SetConnectionString((ReportItemBase)reportInstance);
			return CreateInstanceReportSource(reportInstance, typeReportSource);
		}
	
		throw new NotImplementedException("Handler for the used ReportSource type is not implemented.");
	}
	
	ReportSource CreateInstanceReportSource(IReportDocument report, ReportSource originalReportSource)
	{
		var instanceReportSource = new InstanceReportSource { ReportDocument = report };
		instanceReportSource.Parameters.AddRange(originalReportSource.Parameters);
		return instanceReportSource;
	}
	
	void ValidateReportSource(string value)
	{
		if (value.Trim().StartsWith("="))
		{
			throw new InvalidOperationException("Expressions for ReportSource are not supported when changing the connection string dynamically");
		}
	}
	
	Report UnpackageReport(UriReportSource uriReportSource)
	{
		var reportPackager = new ReportPackager();
		using (var sourceStream = System.IO.File.OpenRead(uriReportSource.Uri))
		{
			var report = (Report)reportPackager.UnpackageDocument(sourceStream);
			return report;
		}
	}
	
	Report DeserializeReport(UriReportSource uriReportSource)
	{
		var settings = new System.Xml.XmlReaderSettings();
		settings.IgnoreWhitespace = true;
		using (var xmlReader = System.Xml.XmlReader.Create(uriReportSource.Uri, settings))
		{
			var xmlSerializer = new Telerik.Reporting.XmlSerialization.ReportXmlSerializer();
			var report = (Telerik.Reporting.Report)xmlSerializer.Deserialize(xmlReader);
			return report;
		}
	}
	
	Report DeserializeReport(XmlReportSource xmlReportSource)
	{
		var settings = new System.Xml.XmlReaderSettings();
		settings.IgnoreWhitespace = true;
		var textReader = new System.IO.StringReader(xmlReportSource.Xml);
		using (var xmlReader = System.Xml.XmlReader.Create(textReader, settings))
		{
			var xmlSerializer = new Telerik.Reporting.XmlSerialization.ReportXmlSerializer();
			var report = (Telerik.Reporting.Report)xmlSerializer.Deserialize(xmlReader);
			return report;
		}
	}
	
	void SetConnectionString(ReportItemBase reportItemBase)
	{
		if (reportItemBase.Items.Count < 1)
			return;
	
		if (reportItemBase is Report)
		{
			var report = (Report)reportItemBase;
	
			if (report.DataSource is SqlDataSource)
			{
				var sqlDataSource = (SqlDataSource)report.DataSource;
				sqlDataSource.ConnectionString = connectionString;
			}
			foreach (var parameter in report.ReportParameters)
			{
				if (parameter.AvailableValues.DataSource is SqlDataSource)
				{
					var sqlDataSource = (SqlDataSource)parameter.AvailableValues.DataSource;
					sqlDataSource.ConnectionString = connectionString;
				}
			}
		}
	
		foreach (var item in reportItemBase.Items)
		{
			//recursively set the connection string to the items from the Items collection
			SetConnectionString(item);
	
			if (item is SubReport)
			{
				var subReport = (SubReport)item;
				subReport.ReportSource = this.UpdateReportSource(subReport.ReportSource);
				continue;
			}
	
			//Covers all data items(Crosstab, Table, List, Graph, Map and Chart)
			if (item is DataItem)
			{
				var dataItem = (DataItem)item;
				if (dataItem.DataSource is SqlDataSource)
				{
					var sqlDataSource = (SqlDataSource)dataItem.DataSource;
					sqlDataSource.ConnectionString = connectionString;
					continue;
				}
			}
		}
	}
}
```

```VB.NET
Imports Telerik.Reporting
  
Class ReportConnectionStringManager
	ReadOnly connectionString As String
	
	Public Sub New(connectionString As String)
		Me.connectionString = connectionString
	End Sub
	
	Public Function UpdateReportSource(sourceReportSource As ReportSource) As ReportSource
		If TypeOf sourceReportSource Is UriReportSource Then
			Dim uriReportSource = DirectCast(sourceReportSource, UriReportSource)
			' unpackage TRDP report
			Dim reportInstance = UnpackageReport(uriReportSource)
			' or deserialize TRDX report(legacy format)
			' var reportInstance = DeserializeReport(uriReportSource);
			ValidateReportSource(uriReportSource.Uri)
			Me.SetConnectionString(reportInstance)
			Return CreateInstanceReportSource(reportInstance, uriReportSource)
		End If
	
		If TypeOf sourceReportSource Is XmlReportSource Then
			Dim xml = DirectCast(sourceReportSource, XmlReportSource)
			ValidateReportSource(xml.Xml)
			Dim reportInstance = Me.DeserializeReport(xml)
			Me.SetConnectionString(reportInstance)
			Return CreateInstanceReportSource(reportInstance, xml)
		End If
	
		If TypeOf sourceReportSource Is InstanceReportSource Then
			Dim instanceReportSource = DirectCast(sourceReportSource, InstanceReportSource)
			Me.SetConnectionString(DirectCast(instanceReportSource.ReportDocument, ReportItemBase))
			Return instanceReportSource
		End If
	
		If TypeOf sourceReportSource Is TypeReportSource Then
			Dim typeReportSource = DirectCast(sourceReportSource, TypeReportSource)
			Dim typeName = typeReportSource.TypeName
			ValidateReportSource(typeName)
			Dim reportType = Type.[GetType](typeName)
			Dim reportInstance = DirectCast(Activator.CreateInstance(reportType), Report)
			Me.SetConnectionString(DirectCast(reportInstance, ReportItemBase))
			Return CreateInstanceReportSource(reportInstance, typeReportSource)
		End If
	
		Throw New NotImplementedException("Handler for the used ReportSource type is not implemented.")
	End Function
	
	Private Function CreateInstanceReportSource(report As IReportDocument, originalReportSource As ReportSource) As ReportSource
		Dim instanceReportSource = New InstanceReportSource() With { _
			.ReportDocument = report _
		}
		InstanceReportSource.Parameters.AddRange(originalReportSource.Parameters)
		Return InstanceReportSource
	End Function
	
	Public Sub ValidateReportSource(value As String)
		If value.Trim().StartsWith("=") Then
			Throw New InvalidOperationException("Expressions for ReportSource are not supported when changing the connection string dynamically")
		End If
	End Sub
	
	Private Function UnpackageReport(uriReportSource As UriReportSource) As Report
		Dim reportPackager = New ReportPackager()
		Using sourceStream = System.IO.File.OpenRead(uriReportSource.Uri)
			Dim report = DirectCast(reportPackager.UnpackageDocument(sourceStream), Report)
			Return report
		End Using
	End Function
	
	Public Function DeserializeReport(uriReportSource As UriReportSource) As Report
		Dim settings = New System.Xml.XmlReaderSettings()
		settings.IgnoreWhitespace = True
		Using xmlReader = System.Xml.XmlReader.Create(uriReportSource.Uri, settings)
			Dim xmlSerializer = New Telerik.Reporting.XmlSerialization.ReportXmlSerializer()
			Dim report = DirectCast(xmlSerializer.Deserialize(xmlReader), Telerik.Reporting.Report)
			Return report
		End Using
	End Function
	
	Public Function DeserializeReport(xmlReportSource As XmlReportSource) As Report
		Dim settings = New System.Xml.XmlReaderSettings()
		settings.IgnoreWhitespace = True
		Dim textReader = New System.IO.StringReader(xmlReportSource.Xml)
		Using xmlReader = System.Xml.XmlReader.Create(textReader, settings)
			Dim xmlSerializer = New Telerik.Reporting.XmlSerialization.ReportXmlSerializer()
			Dim report = DirectCast(xmlSerializer.Deserialize(xmlReader), Telerik.Reporting.Report)
			Return report
		End Using
	End Function
	
	Public Sub SetConnectionString(reportItemBase As ReportItemBase)
		If reportItemBase.Items.Count < 1 Then
			Return
		End If
	
		If TypeOf reportItemBase Is Report Then
			Dim report = DirectCast(reportItemBase, Report)
	
			If TypeOf report.DataSource Is SqlDataSource Then
				Dim sqlDataSource = DirectCast(report.DataSource, SqlDataSource)
				sqlDataSource.ConnectionString = connectionString
			End If
			For Each parameter As Telerik.Reporting.ReportParameter In report.ReportParameters
				If TypeOf parameter.AvailableValues.DataSource Is SqlDataSource Then
					Dim sqlDataSource = DirectCast(parameter.AvailableValues.DataSource, SqlDataSource)
					sqlDataSource.ConnectionString = connectionString
				End If
			Next
		End If
	
		For Each item As Telerik.Reporting.ReportItemBase In reportItemBase.Items
			'recursively set the connection string to the items from the Items collection
			SetConnectionString(item)
	
			If TypeOf item Is SubReport Then
				Dim subReport = DirectCast(item, SubReport)
				subReport.ReportSource = Me.UpdateReportSource(subReport.ReportSource)
				Continue For
			End If
	
			'Covers all data items(Crosstab, Table, List, Graph, Map and Chart)
			If TypeOf item Is DataItem Then
				Dim dataItem = DirectCast(item, DataItem)
				If TypeOf dataItem.DataSource Is SqlDataSource Then
					Dim sqlDataSource = DirectCast(dataItem.DataSource, SqlDataSource)
					sqlDataSource.ConnectionString = connectionString
					Continue For
				End If
	
			End If
		Next
	End Sub
End Class
```

## Notes

When navigating to a Standalone designer report (.trdp, .trdx, .trbp) the paths to the reports will be resolved with respect to the application, not with respect to the main report. This may cause broken *NavigateToReport* Actions when the report is not in the main folder of the application. To resolve the issue it will be necessary to replace the base path from the UriReportSource.Uri with the actual one (path to the application main folder).

Connection string can be modified run time without extra code, based on Report Parameter: [Change Connection String dynamically through a report parameter](https://www.telerik.com/products/reporting/documentation/knowledge-base/how-to-pass-connectionstring-to-report-dynamically-through-report-parameter).