Can't dynamically add controlvalidation to textbox - asp.net

Question

After several searches on the Internet finally decided to drop a question.
At runtime I want the following to happen.
If you push a button a textbox will be added to the controls and a custom validator must be attached to the textbox and fire.
It does not fire. Why?
Here is my code
Thank you for looking into this.
public partial class WebUserControl1 : System.Web.UI.UserControl
{
CustomValidator rv2 = new CustomValidator();
protected void Page_Init(object sender, EventArgs e)
{
if (!IsPostBack)
{
rv2.ID = "rev2";
rv2.ErrorMessage = "Not numeric input";
rv2.ClientValidationFunction = "";
rv2.ServerValidate += new ServerValidateEventHandler(GetalValidator);
Controls.Add(rv2);
}
}
protected void ButtonClick(object sender, EventArgs args)
{
TextBox tb1 = new TextBox();
tb1.ID = "tb2";
tb1.Visible = true;
tb1.Width = 30;
this.Controls.Add(tb1);`enter code here`
rv2.EnableClientScript = false;
rv2.ControlToValidate = "tb2";
}
private bool IsNumber(string someText)
{
int number;
bool result = Int32.TryParse(someText, out number);
return result;
}
protected void GetalValidator(object source, ServerValidateEventArgs args)
{
args.IsValid = IsNumber(args.Value);
}
}

Answer 1

here is part of code thorugh which you can add validation on your dynamically created control.
TextBox tb1 = new TextBox();
tb1.ID = "tb2";
tb1.Visible = true;
tb1.Width = 30;
RequiredFieldValidator regfv = new RequiredFieldValidator();
regfv.ID = "regfv";
regfv.ControlToValidate = tb1.ID;
regfv.ErrorMessage = "My Error";
this.Controls.Add(tb1);
this.Controls.Add(regfv);