C＃，如何在foreach控制循环期间获取HTML生成的文本框值，然后显示结果？

Question

Behind the code C#, when the user select 3(dropdownlist) then press execute button, it will auto generate 3 textboxes. After user fill out names on 3 textboxes then click request button, I want the 3 names that user entered display on different result textbox. How do I do that?

Here are C# codes,

protected void ExecuteCode_Click(object sender, EventArgs e)
{    

     int amount = Convert.ToInt32(DropDownListIP.SelectedValue);

            for (int num = 1; num <= amount; num++)
            {
                HtmlGenericControl div = new HtmlGenericControl("div");
                TextBox t = new TextBox();
                t.ID = "textBoxName" + num.ToString();
                div.Controls.Add(t);
                div1.Controls.Add(div);
            }

            ButtonRequest.Visible = true;
}

    protected void ButtonRequest_Click(object sender, EventArgs e)
        {
            string str = "";
            foreach (Control c in phDynamicTextBox.Controls)
            {
                try
                {
                    TextBox t = (TextBox)c;

                    // gets textbox ID property
                    //Response.Write(t.ID);
                    str = t.Text;
                }
                catch
                {

                }
            }

            TextBoxFinal.Text = str;

        }

Then HTML codes,

<div id="div1" runat="server">
        <asp:PlaceHolder ID="phDynamicTextBox" runat="server" />
        </div>

Answer 1

One option is: when you create the textbox you save the Id in a list in session, then you through the list and use it:

TextBox myTextbox = (TextBox)FindControl("name");

example:

    List<string> list = (List<string>)Session["myList"];
    TextBox myTextbox;
    foreach (string item in list)
    {
        myTextbox = (TextBox)FindControl(item);
        //in myTextbox you have the atribute Text with the informatcion 
    }

Sorry for my english.

Answer 2

you cannot access to control that create dynamically on postback, but you can try get input value from request like this

protected void ExecuteCode_Click(object sender, EventArgs e)
{    
    List<string> tbids = new List<string>();
    int amount = Convert.ToInt32(DropDownListIP.SelectedValue);

        for (int num = 1; num <= amount; num++)
        {
            HtmlGenericControl div = new HtmlGenericControl("div");
            TextBox t = new TextBox();
            t.ID = "textBoxName" + num.ToString();
            div.Controls.Add(t);
            phDynamicTextBox.Controls.Add(div);
            tbids.Add(t.ID);
        }
        Session["tbids"] = tbids;
        ButtonRequest.Visible = true;
}

protected void ButtonRequest_Click(object sender, EventArgs e)
    {
        string str = "";
        var tbids = (List<string>)Session["tbids"];
        foreach (var id in tbids)
        {
            try
            {
                str += Request[id]+" "; //here get value tb with id;
            }
            catch
            {

            }
        }

        TextBoxFinal.Text = str;

    }