Retrieving values from dynamically created controls Label in asp .net

Question

I have created Label controls dynamically on button click:

protected void createDynamicLabels_Click(object sender, EventArgs e)
{
    int n = 5;
    for (int i = 0; i < n; i++)
    {
        Label MyLabel = new Label();
        MyLabel.ID = "lb" + i.ToString();
        MyLabel.Text = "Labell: " + i.ToString();
        MyLabel.Style["Clear"] = "Both";
        MyLabel.Style["Float"] = "Left";
        MyLabel.Style["margin-left"] = "100px";

        Panel1.Controls.Add(MyLabel);
    }
}

When I tried to read back fro another button I see Label Control returned null

Label str = (Label)Panel1.FindControl("lb" + i.ToString());

not sure what went wrong here

protected void bReadDynValue_Click(object sender, EventArgs e)
{

  int n = 5;
    for (int i = 0; i < n; i++)
    {
        Label str = (Label)Panel1.FindControl("lb" + i.ToString());
        lbGetText.Text = str.Text;
    }


}

Answer 1

this is the issue of every time page load event. ASP.net fire every time page load event when any button is click.

suppose in this example..

protected void Page_Load(object sender, EventArgs e)
{

    if(!IsPostBack)
        createDynamicLabels();
}


private void createDynamicLabels()
    {
        int n = 5;
        for (int i = 0; i < n; i++)
        {
            Label MyLabel = new Label();
            MyLabel.ID = "lb" + i.ToString();
            MyLabel.Text = "Labell: " + i.ToString();
            MyLabel.Style["Clear"] = "Both";
            MyLabel.Style["Float"] = "Left";
            MyLabel.Style["margin-left"] = "100px";

            Panel1.Controls.Add(MyLabel);


        }
    }

protected void bReadDynValue_Click(object sender, EventArgs e)
{

    int n = 5;
    for (int i = 0; i < n; i++)
    {
        Label str = (Label)Panel1.FindControl("lb" + i.ToString());
        lbGetText.Text = str.Text;
    }


}

when Button trigger Page doesn't have any label because it is made on runtime. and Page doesn't find particular label. if you tried above code it is run properly.

 protected void Page_Load(object sender, EventArgs e)
{

        createDynamicLabels();
}


private void createDynamicLabels()
    {
        int n = 5;
        for (int i = 0; i < n; i++)
        {
            Label MyLabel = new Label();
            MyLabel.ID = "lb" + i.ToString();
            MyLabel.Text = "Labell: " + i.ToString();
            MyLabel.Style["Clear"] = "Both";
            MyLabel.Style["Float"] = "Left";
            MyLabel.Style["margin-left"] = "100px";

            Panel1.Controls.Add(MyLabel);


        }
    }

protected void bReadDynValue_Click(object sender, EventArgs e)
{

    int n = 5;
    for (int i = 0; i < n; i++)
    {
        Label str = (Label)Panel1.FindControl("lb" + i.ToString());
        lbGetText.Text = str.Text;
    }


}

in this Example code find label every time because every time it can make labels for this page.