programatically pass the connection string to the ssrs reports

hi... to all
i've created ssrs reports local following is my code..
public void source(string tbname,string Rptname)
{
ReportViewer1.Visible = true;
string myQuery = "select * from " + tbname;
SqlConnection myConnection = new SqlConnection(ConnectionString);
SqlCommand myCommand = new SqlCommand(myQuery, myConnection);
myCommand.Connection.Open();
SqlDataAdapter da = new SqlDataAdapter(myCommand);
DataSet dt = new DataSet();
da.Fill(dt);


//ReportParameter[] p = new ReportParameter[1];
//p[1] = new ReportParameter("@p_dno", "5");
//this.ReportViewer1.LocalReport.SetParameters(p);
//DataSet dt = new DataSet();
//dt = p;
ReportViewer1.LocalReport.ReportPath = Rptname + ".rdlc" ;
ReportViewer1.ProcessingMode = Microsoft.Reporting.WebForms.ProcessingMode.Local;
ReportDataSource datasource = new ReportDataSource("employeeDataSet_" + tbname , dt.Tables[0]);
ReportViewer1.LocalReport.DataSources.Clear();
ReportViewer1.LocalReport.DataSources.Add(datasour ce);

}
now it works good..
as i expected...

but i want to pass the datasource connection string from here is there any
way to pass the datasource programatically....