title: Crystal report throw error when reused
body: <p>I do a programmatically bind to my crystal report viewr like</p>
  
  <pre><code>DataTable orderDtSrc = GetDataFromdb(txtOrderNo.Text);     
  rptViewer.ReportSource = new ReportDocument();
                  if (orderDtSrc != null)
                  {
                      ReportDocument report = new ReportDocument();
                      report.Load(Server.MapPath("Design/MyReport.rpt"));
                      report.SetDataSource(orderDtSrc);
                      report.SummaryInfo.ReportTitle = "Report No-" + orderDtSrc.Rows[0]["OrderNumber"].ToString();
                      rptViewer.ReportSource = report;
                      rptViewer.DataBind();
                  }
  </code></pre>
  
  <p>So It will get the data throw the <code>GetDataFromdb(txtOrderNo.Text);</code> which get data by order number provided by user.</p>
  
  <p>first call it will get the report and bind the viewer with no problem then if I put a new order number in the textbox and then click on show report button which call the previous function I got this exception.</p>
  
  <pre><code>Value cannot be null. Parameter name: inputString
  </code></pre>