c# - Placeholder controls count always return 0 in button click -

i created textbox dynamically using code below , entered text in textbox. want read control's id while adding text database. how can id of textbox on click of button.

for (int = 0; < dv_count; i++) {     textbox txt_box = new textbox();     txt_box.text = "";     txt_box.id = "s" + i;     placeholder1.controls.add(txt_box); }  protected void btn_act_proceed_click(object sender, eventargs e) {     int count = placeholder1.controls.count; //always return 0      if (count > 0)     {         int dv_count = count / 2;          (int = 0; < dv_count; i++)         {             textbox  lbl_type = (textbox )placeholder1.findcontrol("s" + i);         }     } } 

try

in aspx page

<div runat="server" id="plcholder"> </div> <asp:button id="button1" runat="server" text="button" onclick="button1_click" /> 

now in code behind

protected void page_load(object sender, eventargs e) {     populate(); }  public void populate() {     (int = 0; < 3; i++)     {         textbox tb = new textbox();         tb.id = "s" + i;         tb.text = "hello" + i;         plcholder.controls.add(tb);     } }  protected void button1_click(object sender, eventargs e) {     int cont = plcholder.controls.count;      (int = 0; < cont-1; i++)     {         textbox tx = (textbox)plcholder.findcontrol("s" + i);         response.write(tx.text);     } }