Question

Im creating a survey page, this page pulls from the database to display questions based on their type, For each type I have created a user control. At Page_Load, I place the User Control in a placeholder like this:- (QNO is a session i set to 0 on the previous page, just to start the question order)

protected void Page_Load(object sender, EventArgs e)
        {

            SqlConnection Connection = DatabaseConnection.GetSurveySystemConnection();

            string sqlquery = "SELECT Q.[ID], Q.[Question_Order], Q.[Question], QT.[Type_Desc] FROM [Questions] Q Inner join Question_Type QT On Q.Type_ID= QT.ID Where Q.[Survey_ID] =" + Session["Survey_ID"] + "Order by Question_Order";

            SqlCommand cmd = new SqlCommand(sqlquery, Connection);
            cmd.CommandType = CommandType.Text;
            SqlDataAdapter da = new SqlDataAdapter();
            da.SelectCommand = cmd;
            DataTable DT = new DataTable();
            da.Fill(DT);

            if (DT != null)
            {
                Session["Count"] = DT.Rows.Count;
                QuestionLabel.Text = String.Format("{0}.{1}", DT.Rows[Convert.ToInt32(Session["QNO"])]["Question_Order"].ToString(), DT.Rows[Convert.ToInt32(Session["QNO"])]["Question"].ToString());
                Session["Question_ID"] = DT.Rows[Convert.ToInt32(Session["QNO"])]["ID"].ToString();

                if (DT.Rows[Convert.ToInt32(Session["QNO"])]["Type_Desc"].ToString() == "Multiple Choice")
                {
                    Control uc = Page.LoadControl("UserControls/MultipleChoice.ascx");
                    PlaceHolder2.Controls.Add(uc);
                }
                else if (DT.Rows[Convert.ToInt32(Session["QNO"])]["Type_Desc"].ToString() == "Single Choice")
                {
                    Control uc = Page.LoadControl("UserControls/SingleChoice.ascx");
                    PlaceHolder2.Controls.Add(uc);
                }
                else if (DT.Rows[Convert.ToInt32(Session["QNO"])]["Type_Desc"].ToString() == "Yes/No")
                {
                    Control uc = Page.LoadControl("UserControls/YesOrNo.ascx");
                    PlaceHolder2.Controls.Add(uc);
                }
                else if (DT.Rows[Convert.ToInt32(Session["QNO"])]["Type_Desc"].ToString() == "Agree/Disagree")
                {
                    Control uc = Page.LoadControl("UserControls/AgreeDisagree");
                    PlaceHolder2.Controls.Add(uc);
                }
                else if (DT.Rows[Convert.ToInt32(Session["QNO"])]["Type_Desc"].ToString() == "Rating")
                {
                    Control uc = Page.LoadControl("UserControls/Rating.ascx");
                    PlaceHolder2.Controls.Add(uc);
                }
                else if (DT.Rows[Convert.ToInt32(Session["QNO"])]["Type_Desc"].ToString() == "Open Ended")
                {
                    Control uc = Page.LoadControl("UserControls/OpenEnded.ascx");
                    PlaceHolder2.Controls.Add(uc);
                }
            }
        }

Now, lets say for the type “Open Ended”, it displays a textbox in the usercontrol, I want to access this textbox and retrieve the text inside it and put it in another textbox at the push of a button, I created a static textbox on the page and called it ViewTextBox.
This is what i tried:-

 protected void Button1_Click(object sender, EventArgs e)
            {
    TextBox t = Controls[0].Controls[3].Controls[11].Controls[5].Controls[0].Controls[0] as TextBox;
    ViewTextBox.Text = t.Text; //"Object reference not set to an instance of an object."
            }

Any Ideas? I dug my way through the controls on the page to find the textbox in the usercontrol :-

Response.Write(Controls[0].Controls[3].Controls[11].Controls[5].Controls[0].Controls[0].ID);

And the ID comes up as the textbox im looking for. The textbox in the usercontrol is called “OpenEndedTextBox”

Answer 1

Instead of digging like that, I would suggest creating a Method or Property in your user control to get that text from your User Control like this

public string GetAnsweredText()
{
   return this.AnswerTextBox.Text;
}

and call this Method in your button’s click event in your page containing that user control like this

protected void Button1_Click(object sender, EventArgs e)
{
   UC_SurveyControl control = this.Controls[0] as UC_SurveyControl;
   if (control != null)
       string answer = control.GetAnsweredText();
}