how to encode and decode the url querystring passed in anchor tag in asp.net

This way

<a href='../Product_Page.aspx?id=<%# Server.UrlEncode(Eval("PSubCatId"))%>&scat=<%#Server.UrlEncode(Eval("SName"))%>&cat=<%#Server.UrlEncode(Eval("Name"))%>&cid=<%#Server.UrlEncode(Eval("PCatId"))%>' style="text-decoration:none"><asp:Label ID="Label2"  runat="server" Text='<%#Eval("SubCatName")%>' ></asp:Label> </a>

Hello, 

 Thanks for your quick response. 

Server.UrlEncodeHttpUtility.UrlEncodewas not working in a href tag . I replaced it with HttpUtility.UrlEncode in a href tag. Now it is working but my problem is not solved.

My real problem is that i am passing the category and subcategory name in querystring from Page "A" to Page "B". I am showing the Page Name and Page Tilte on Page "B" from the data in querystring. It is showing correct but if someone is on the page "B" and he changes the data in Querystring the PageName and Page Title is changing.

   What i should do to resolve this issue. I thought that encoding and decoding will solve my issue but it did not. Please suggest me what i should do?

Make use of session if you want to avoid this issue. Since even you encrypt the Querystring still anyone change change it

I used the session before using query string but the problem with the session was that if my client sends this url link to other user then if  other user clicks on the url link then there  will  be error due to use of sesaion on this page or simply we copy this url and paste this url to another browser then error occurs due to the  use of session on that page. now what i should do. please suggest me.

Then querystring is the only option and unfortunately thre is nothing much you can do with querystring as user is free to change it