How To Use The FindControl Function To Find A Dynamically Generated Control

Jun 10, 2010

I have a PlaceHolder control inside of a ListView that I am using to render controls from my code behind. The code below adds the controls:

TextBox tb = new TextBox();
tb.Text = quest.Value;
tb.ID = quest.ShortName.Replace(" ", "");

I am using the following code to retrieve the values that have been entered into the TextBox:

foreach (ListViewDataItem di in lv_Questions.Items)
int QuestionId = Convert.ToInt32(((HiddenField)di.FindControl("hf_QuestionId")).Value);
Question quest = dc.Questions.Single(q => q.QuestionId == QuestionId);
TextBox tb = ((TextBox)di.FindControl(quest.ShortName.Replace(" ","")));
//tb is always null!

But it never finds the control. I've looked at the source code for the page and the control i want has the id:


For some reason when I look at the controls in the ListViewDataItem it has the ClientID:


Why would it be changing Numberofacres to ctl00? Is there any way to work around this?


Just to clarify, I am databinding my ListView in the Page_Init event. I then create the controls in the ItemBound event for my ListView. But based on what @Womp and MSDN are saying the controls won't actually be created until after the Load event (which is after the Page_Init event) and therefore are not in ViewState? Does this sound correct?

If so am I just SOL when it comes to retrieving the values in my dynamic controls from my OnClick event?


So i changed the code i had in my Page_Init event from:

protected void Page_Init(object sender, EventArgs e)
if (!this.IsPostBack)
//databind lv_Questions


protected void Page_Init(object sender, EventArgs e)
//databind lv_Questions

And it fixed my problem. Still a little confused as to why I want to databind regardless of whether it's a postback or not but the issue is resolved.

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