在回发时保持动态控件不起作用

Question

我收到此错误但未发现问题：

  

对象引用未设置为对象的实例。

我的代码：

Page Init：

else if (Request.QueryString["CompanyID"] != null)
{
   pnlComp.Visible = true;
   if (Convert.ToString(ViewState["Generated"]) != "true")
   {
      createCompSite();
      ViewState["Generated"] = "true";
   }                
}

页面加载：

 Verification.Check();
 if (!IsPostBack)
 {
    sFilter= null;
    FillGridviewAndValues();
 }
 if (Convert.ToString(ViewState["Generated"]) == "true")
    createCompSite();

功能：

TableHeaderRow tHRow = new TableHeaderRow();
TableHeaderCell tHeader = new TableHeaderCell();
tHeader.Text = dr.Field<string>("Loc");
tHRow.Cells.Add(tHeader);
tblCompLoc1.Rows.Add(tHRow);

DataTable dtCat = new DataTable();
dtCat = SQLCon.SQLCommand_DokuTool("SELECT CL.ID, C.CatName FROM TBL_Ref_CatLoc AS CL, TBL_Category AS C WHERE C.CatID = CL.CatID AND CL.LocID = '" + dr.Field<Guid>("ID").ToString() + "' AND CL.Approved='True' ORDER BY CatName ASC");

foreach (DataRow dr2 in dtCat.Rows)
{
   //Working as plain Text
   //TableRow tRow = new TableRow();
   //TableCell tCell = new TableCell();
   //tCell.Text = dr2.Field<string>("CatName");
   //tRow.Cells.Add(tCell);
   //tblCompLoc1.Rows.Add(tRow);


   //Not working as Hyperlink or Btn
     TableRow tRow = new TableRow();
     TableCell tCell = new TableCell();
     HyperLink hl = new HyperLink();
     hl.EnableViewState=true;
     hl.Text = dr2.Field<string>("CatName");
     string gLocID = SQLCon.SQLCommand_User("SELECT ID FROM TBL_Location WHERE fCompanyID = '"+sRequest+"' AND City + ', ' + Street1 ='"+tHeader.Text+"'").Rows[0].Field<Guid>("ID").ToString();
     string gCatID = SQLCon.SQLCommand_DokuTool("SELECT CatID FROM TBL_Category WHERE CatName='"+hl.Text+"'").Rows[0].Field<Guid>("CatID").ToString();
     string sRequestedCat = SQLCon.SQLCommand_DokuTool("SELECT ID FROM TBL_Ref_CatLoc WHERE LocID = '"+gLocID+"' AND CatID='"+gCatID+"'").Rows[0].Field<Guid>("ID").ToString();                        
     hl.NavigateUrl="~/Default?ID="+sRequestedCat;
     tCell.Controls.Add(hl);
     tRow.Controls.Add(tCell);
     tblCompLoc1.Rows.Add(tRow);
}

我想创建一个从DataBase填充的表，并且在每个站点上看起来可能不同，并且每个表格单元应该具有引导用户的不同链接。表创建从init。页面开始。