How to use .Net controls with HTMLTEXTWRITER

Question

The code mentioned below is part of my webpart on sharepoint 2010.

public class class1 : System.Web.UI.WebControls.WebParts.WebPart
    { 
protected override void Render(HtmlTextWriter writer)
        {
            string s1 = "first";
            string s2 = "second";
            string s3 = "third";

            slist.Add("first");
            slist.Add("second");
            LinkButton b;

            writer.Write("<div id='tblSegment' ><table >");
            foreach (string s in slist)
            {
                //b = new LinkButton();
                //b.Text = s;
                //b.Click += (sender1, e1) => { b_Click(sender, e, s1, s2, s3); };
                writer.Write("<tr><td >");
                writer.Write("<a href=''  >");
                writer.Write(s + "</a>");
                writer.Write("</td></tr>");
            }
            writer.Write("</table></div>");
        }
        void b_Click(object sender, EventArgs e, string s1, string s2, string s3)
        {
            UpdateList(s1,s2,s3);
        }
    public void UpdateList(string ID, string column, string value)
        {
            using (SPSite oSPsite = new SPSite("http://server"))
            {
                using (SPWeb oSPWeb = oSPsite.OpenWeb())
                {
                    oSPWeb.AllowUnsafeUpdates = true;
                    // Fetch the List
                    SPList list = oSPWeb.Lists["UserProfiles"];
                    //create Query
                    SPQuery query = new SPQuery();
                    query.Query = string.Concat(
                                   "<Where><Eq>",
                                      "<FieldRef Name='ID'/>",
                                      "<Value Type='String'>" + ID + "</Value>",
                                   "</Eq></Where>");
                    //get List Item
                    SPListItemCollection listItems = list.GetItems(query);
                    SPListItem item = listItems[0];

                    //update List Item
                    item[column] = value;
                    item.Update();
                    oSPWeb.AllowUnsafeUpdates = false;
                }
            }
        }
}

I am kind of stuck here, what i need to do is to update a sharepoint list item based on some values(s1,s2,s3), for which i have created method UpdateList. I need to call UpdateList method whenever any hyperlink is clicked. I tried to use link buttons but as expected they did not worked(commented) with htmltextwriter, so i added two simple anchor tags. But how to fire the click event now.

I read about system.web.services but unable to make it work. The only option i can think of now is to create a seprate web service with method UpdateList in it kind of thing and make a ajax call to it.

Can any body suggest something else or is it somhow possible to use ASP.Net colrols(eg LinkButton) with Htmltextwriter.

TheKingDave · Answer 1 · 2013-01-21T17:03:06.133

Ok firstly use the OnLoad event rather than Render.

What you need to do is add the LinkButton to the Controls property.

You will find it difficult to get your hyperlink to call updatelist directly without hand coding the postback event.

Edit This works for me:

List<string> slist = new List<string>();
        protected void Page_Load(object sender, EventArgs e)
        {
            string s1 = "first";
            string s2 = "second";
            string s3 = "third";

            slist.Add("first");
            slist.Add("second");
            LinkButton b;


            foreach (string s in slist)
            {
                b = new LinkButton();
                b.Text = s;
                b.Click += (sender1, e1) => { b_Click(sender, e, s1, s2, s3); };

                this.Form.Controls.Add(b);
                this.Form.Controls.Add(new LiteralControl("<br/>"));
            }
        }

        void b_Click(object sender, EventArgs e, string s1, string s2, string s3)
        {
            UpdateList(s1, s2, s3);
        }

        public void UpdateList(string ID, string column, string value)
        {
            // ... enter code here

        }
    }

Replace Page_Load with the load event of you control and you will need to replace this.Form.Controls with this.controls. You can also and in to the literal control instead to give you a space between the links rather than a line break.

what you said is a working solution but i can not change it to onload event, as i already mentioned the code i shared is just a part of solution. For now i have used Sharepoint JS library and everything is working fine....for now atleast — Mohit, Jan 25 '13 at 05:57

How to use .Net controls with HTMLTEXTWRITER

1 Answers1