C＃使用文本框作为“发布” /“便笺”客户端事件

Question

I want a textbox to act like a "post it" or "Sticky memo" just like widget Igoogle or Windows 7 widget.

The idea:

 <asp:TextBox ID="TextBox1" runat="server"> 
 </asp:TextBox>

Every time that user types into the textbox it calls Javascript to save the text into cookies.

Could somebody give me a hint?

Answer 1

This is somewhat quick and dirty but will get you going.

There's plenty of setCookie/getCookie JS snippets around the web. I used these:

http://www.dotnetspark.com/kb/1480-use-cookies-javascript-getcookie-setcookie.aspx

Teh code now:

<input type="text" id="txtMemo" />

<script type="text/javascript">

function setCookie(CookieName, CookieVal, CookieExp, CookiePath, CookieDomain, CookieSecure)
{
     var CookieText = escape(CookieName) + '=' + escape(CookieVal); //escape() : Encodes the String
    CookieText += (CookieExp ? '; EXPIRES=' + CookieExp.toGMTString() : '');
    CookieText += (CookiePath ? '; PATH=' + CookiePath : '');
    CookieText += (CookieDomain ? '; DOMAIN=' + CookieDomain : '');
    CookieText += (CookieSecure ? '; SECURE' : '');

    document.cookie = CookieText;
}

// This functions reads & returns the cookie value of the specified cookie (by cookie name) 
function getCookie(CookieName)
{
    var CookieVal = null;
    if(document.cookie)       //only if exists
    {
           var arr = document.cookie.split((escape(CookieName) + '=')); 
           if(arr.length >= 2)
           {
               var arr2 = arr[1].split(';');
               CookieVal  = unescape(arr2[0]); //unescape() : Decodes the String
           }
    }
    return CookieVal;
}

var memoCookieName = "txtMemo_value";
var memoElementId = "txtMemo";

var memoElement = document.getElementById(memoElementId);

memoElement.value=getCookie(memoCookieName);
memoElement.onkeyup = function() {
    setCookie(memoCookieName,this.value, new Date(new Date().getTime()+1000*60*60*24*30));
};

 </script>

This will work with plain HTML. In your case with ASP.NET markup and controls the ID property has a different meaning, so you need to make your JS aware of the actual client ID. This way for example:

(...)
var memoCookieName = "txtMemo_value";
var memoElementId = "<%= TextBox1.ClientID %>";

var memoElement = document.getElementById(memoElementId);
(...)

Answer 2

Of course. Play with "change" event:

• http://www.w3schools.com/jsref/event_onchange.asp

It's just about using this event and update some cookie that you previously created with JavaScript too.