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Cannot Implicitly Convert Type 'Telerik.Reporting.XXXReportSource'


Product Progress® Telerik® Reporting
Report Viewer HTML5 WebForms Report Viewer


An error is thrown when trying to set the ReportSource of the HTML5 WebForms Report Viewer.

Error Message

Cannot implicitly convert type 'Telerik.Reporting.XXXReportSource' to 'Telerik.ReportViewer.Html5.WebForms.ReportSource'.

Cause\Possible Cause(s)

Trying to set a report source of type Telerik.Reporting.XXXReportSource to the HTML5 WebForms Report Viewer. HTML5 WebForms Report Viewer expects a special report source of type Telerik.ReportViewer.Html5.WebForms.ReportSource.


Set the report viewer's ReportSource to an instance of the Telerik.ReportViewer.Html5.WebForms.ReportSource object type.

protected void Page_Load(object sender, EventArgs e)
    if (!IsPostBack)
        Telerik.ReportViewer.Html5.WebForms.ReportSource reportSource = new Telerik.ReportViewer.Html5.WebForms.ReportSource();
        reportSource.IdentifierType = Telerik.ReportViewer.Html5.WebForms.IdentifierType.UriReportSource;
        reportSource.Identifier = "Report1.trdp";
        reportViewer1.ReportSource = reportSource;
Protected Sub Page_Load(sender As Object, e As EventArgs)
    If Not IsPostBack Then
        Dim reportSource As New Telerik.ReportViewer.Html5.WebForms.ReportSource()
        reportSource.IdentifierType = Telerik.ReportViewer.Html5.WebForms.IdentifierType.UriReportSource
        reportSource.Identifier = "Report1.trdp"
        reportViewer1.ReportSource = reportSource
    End If
End Sub


The HTML5 WebForms Report Viewer works with a client-side report source which is of type Telerik.ReportViewer.Html5.WebForms.ReportSource.

  • ReportSource.IdentifierType property specifies which resolver will be used for resolving the report description string on the server.
  • ReportSource.Identifier property accepts a string that contains information about the report. This string can be a path to a TRDP or TRDX file that can be resolved by ReportFileResolver, an assembly-qualified name of the report class which can be resolved by ReportTypeResolver or custom information which can be resolved by custom report resolver.

See Also

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