This example shows how to connect to data from code. First, load scripts:

@using Stimulsoft.Base
@using Stimulsoft.Report
@using Stimulsoft.Report.Blazor

Next, add buttons:

<div align="center">
    <button class="alert" @onclick="SetFirstDataSet">First dataset</button>
    <button class="alert" @onclick="SetSecondDataSet">Second dataset</button>
</div>
<br />

Then, add report viewer:

<StiBlazorViewer Report="@Report" />

After that, create empty report object and load report template:

@code
{
    private StiReport Report;

    protected override void OnInitialized()
    {
        base.OnInitialized();

        //Create empty report object
        var report = new StiReport();

        //Load report template
        report.Load("Reports/Report.mrt");
    }

...

Next, set first dataset:

...

	private void SetFirstDataSet()
    {
        //Get a copy of the report into a new report object
        var report = this.Report.Clone() as StiReport;
		
        //Delete connections in the report template
        report.Dictionary.Databases.Clear();

        //Load new data from XML file
        var data = new System.Data.DataSet();
        data.ReadXml("Data/Demo1.xml");

        //Register new data in the report template
        report.RegData(data);

        //Synchronize the dictionary with registered data
        //Not necessary if the structure of the loaded data is the same as in the template
        report.Dictionary.Synchronize();

        //Re-render report
        report.Render();
		
        //Assign new report to the Viewer
        this.Report = report;
    }
	
...

Then, set second dataset:

...

	private void SetSecondDataSet()
    {
		//Get a copy of the report into a new report object
		var report = this.Report.Clone() as StiReport;
		
        //Delete connections in the report template
        report.Dictionary.Databases.Clear();

        //Load new data from XML file
        var data = new System.Data.DataSet();
        data.ReadXml("Data/Demo2.xml");

        //Register new data in the report
        report.RegData(data);

        //Synchronize the dictionary with registered data
        //Not necessary if the structure of the loaded data is the same as in the template
        report.Dictionary.Synchronize();

        //Re-render report
        report.Render();
		
        //Assign new report to the Viewer
        this.Report = report;
    }
}

In the screenshot below you can see the result of the sample code: