用户控件的ViewState!

Question

做了一个输入框控件：
[DefaultProperty("Text")]
    [ToolboxData("<{0}:ttttttt runat=server></{0}:ttttttt>")]
    public class ttttttt: WebControl
    {
        [Bindable(true)]
        [Category("Appearance")]
        [DefaultValue("")]
        [Localizable(true)]
        public string Text
        {
            get
            {
                String s = (String)ViewState["Text"];
                return ((s == null)? String.Empty : s);
            }
 
            set
            {
                ViewState["Text"] = value;
            }
        }        public ttttttt()
            : base(HtmlTextWriterTag.Input)
        { }        protected override void AddAttributesToRender(HtmlTextWriter writer)
        {
            base.AddAttributesToRender(writer);
            writer.AddAttribute(HtmlTextWriterAttribute.Type, "text");
            writer.AddAttribute(HtmlTextWriterAttribute.Value, Text);
        }
=================
可是在后台取不到输入的值！

Answer 1

public class ttttttt: WebControl.TextBox 
试试.

Answer 2

if(Page.IsPostBack && Request.Pamas[this.UniqueID]!= null )
{
   this.Text = Request.Pamas[this.UniqueID];
}把这段代码放在OnLoadViewstata之前，

Answer 3

或是在重写Load的时候,并且这时要触发TextChanged事件

Answer 4

....想了下,
只要写在OnSaveViewState之前，并且在你读取该值之前均可,
如果你要在Page_Load中读取，你要写在Control.Load事件发生之前,其它的倒没有什么要紧的

Answer 5

你们人这些原因也不想想，就知道顶,何来讨论楼主的 public string Text
        {
            get
            {
                String s = (String)ViewState["Text"];
                return ((s == null)? String.Empty : s);
            }
 
            set
            {
                ViewState["Text"] = value;
            }
        }
这段代码很清楚的表示，Text属性只有其它代码给它值的时候才会记录当用户改变了值,然后点击submit按钮,谁来改变这个值,这个值依然还是上次给他的那个值
这时应该 看它的值是否在Request 列表中并且在submit之后由自己给

Answer 6

zyug(LovlyPuppy) : 对呀，我就想知道javascript中能吧值存到SESSION吗？

Answer 7

hdt(倦怠) 的方法是对的，我把源代码贴出来供大家参考吧：
 public String Text
        {
            get
            {
                return (String)ViewState["Text"];
            }            set
            {
                ViewState["Text"] = value;
            }
        }        public ttttttt()
            : base(HtmlTextWriterTag.Input)
        { }        public event EventHandler TextChanged;        public virtual bool LoadPostData(string postDataKey,
           NameValueCollection postCollection)
        {            String presentValue = Text;
            String postedValue = postCollection[postDataKey];            if (presentValue == null || !presentValue.Equals(postedValue))
            {
                Text = postedValue;
                return true;
            }            return false;
        }        public virtual void RaisePostDataChangedEvent()
        {
            OnTextChanged(EventArgs.Empty);
        }        protected virtual void OnTextChanged(EventArgs e)
        {
            if (TextChanged != null)
                TextChanged(this, e);
        }        protected override void AddAttributesToRender(HtmlTextWriter writer)
        {
            writer.AddAttribute(HtmlTextWriterAttribute.Type, "input");
            writer.AddAttribute(HtmlTextWriterAttribute.Value, Text);
            writer.AddAttribute(HtmlTextWriterAttribute.Name, this.UniqueID);
        }
==========================
 writer.AddAttribute(HtmlTextWriterAttribute.Name, this.UniqueID);
这行比较重要！