Getting the old value of a asp.net control on postback

Question

I want to be able to find the old value of a asp.net control (textbox, checkbox etc) without relying on events (e.g. OnTextChange event). Something like "someTextboxControl.OldText" would be perfect! I imagine that it is stored in the viewstate and need to somehow get at it via a custom control. Any ideas?

Answer 1

you could iterate Request.Form collection ffor details how you can iterate this check this link http://msdn.microsoft.com/en-us/library/ms525985.aspx

Answer 2

public class TextBoxEx:System.Web.UI.WebControls.TextBox
    {
        public string OldText { get; set; }


        protected override bool LoadPostData(string postDataKey, System.Collections.Specialized.NameValueCollection postCollection)
        {
            OldText = Text;
            return base.LoadPostData(postDataKey, postCollection);
        }

    }