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c#sharepointcontrolsweb-parts

Add controls to this.Controls.Add( results controls at the beginning of my page


I am using c# asp.net and building a SharePoint visual webpart. I have this method which is adding some controls to the page:

private string RSSFile = @"http://www.myCompany.com/xml_feed.xml";

        protected override void CreateChildControls()
        {
            base.CreateChildControls();

            // introductionText
            HtmlGenericControl introductionText = new HtmlGenericControl("p");
            introductionText.InnerHtml = "De volgende vacatures staan momenteel open:";
            this.Controls.Add(introductionText);

            // table
            HtmlGenericControl mainTable = new HtmlGenericControl("table");
            mainTable.Attributes.Add("cellpadding", "10");
            HtmlGenericControl tr1 = new HtmlGenericControl("tr");
            Controls.Add(mainTable);
            mainTable.Controls.Add(tr1);

            // header columns
            tr1.InnerHtml = "<th style=\"text-align:left;\">Vacature</th><th style=\"text-align:left;\">Standplaats</th><th style=\"text-align:left;\">Uren</th>";

            // load xml file
            // TODO load from webpart property
            var xmlSource = XElement.Load(RSSFile);

            // get all file elements
            IEnumerable<XElement> q =
                (from c in xmlSource.Descendants("vacature")
                 select c).ToArray();
            // TODO filter on date
            //where (string)c.Element("publish") == "True"
            //orderby c.Element("name").Value, c.Element("version").Value

            // loop into each file element and get values
            foreach (XElement c in q)
            {
                HtmlGenericControl tr2 = new HtmlGenericControl("tr");
                mainTable.Controls.Add(tr2);

                // title with hyperlink
                HtmlGenericControl td1 = new HtmlGenericControl("td");
                td1.Style.Add("vertical-align", "top");
                td1.InnerHtml = string.Format("<a href=\"Home.aspx?vacatureNr={0}\">{1}</a>", c.Element("vacaturenr").Value, c.Element("titel").Value);
                tr2.Controls.Add(td1);

                // location
                HtmlGenericControl td2 = new HtmlGenericControl("td");
                td2.Style.Add("vertical-align", "top");
                td2.InnerHtml = c.Element("regios").Value;
                tr2.Controls.Add(td2);

                // uren
                HtmlGenericControl td3 = new HtmlGenericControl("td");
                td3.Style.Add("vertical-align", "top");
                td3.InnerHtml = string.Concat(c.Element("min_uren").Value, " - ", c.Element("max_uren").Value);
                tr2.Controls.Add(td3);
            }

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

Like you see I have an ahref which is referenced to the same page and adds a querystring "vacatureNr". In the pageload I check if this "vacatureNr" is filled. If it is filled I would like to add extra controls to my page. It workds, but the controls are added before the controls which are added in the method "CreateChildControls". How can I add these controls after the controls which are already added in the method "CreateChildControls"?

protected void Page_Load(object sender, EventArgs e)
        {
            string vacatureNr = Request.QueryString["vacatureNr"];
            if(!string.IsNullOrEmpty(vacatureNr))
            {
                this.Controls.Clear();

                HtmlGenericControl table = new HtmlGenericControl("table");
                HtmlGenericControl tr1 = new HtmlGenericControl("tr");
                HtmlGenericControl td1 = new HtmlGenericControl("td");
                HtmlGenericControl td2 = new HtmlGenericControl("td");
                td1.InnerHtml = "<strong>Inzet in uren:</strong>";
                td2.InnerHtml = "24-32";
                tr1.Controls.Add(td1);
                tr1.Controls.Add(td2);
                table.Controls.Add(tr1);

                HtmlGenericControl tr2 = new HtmlGenericControl("tr");
                HtmlGenericControl td3 = new HtmlGenericControl("td");
                HtmlGenericControl td4 = new HtmlGenericControl("td");
                td3.InnerHtml = "<strong>Standplaats:</strong>";
                td4.InnerHtml = "Egmond aan Zee";
                tr2.Controls.Add(td3);
                tr2.Controls.Add(td4);
                table.Controls.Add(tr2);

                HtmlGenericControl tr3 = new HtmlGenericControl("tr");
                HtmlGenericControl td5 = new HtmlGenericControl("td");
                HtmlGenericControl td6 = new HtmlGenericControl("td");
                td5.InnerHtml = "<strong>Aard van dienstverband:</strong>";
                td6.InnerHtml = "Bepaalde tijd";
                tr3.Controls.Add(td5);
                tr3.Controls.Add(td6);
                table.Controls.Add(tr3);

                this.Controls.Add(table);
            }
        }

Solution

  • The CreateChildControls method will always be fired before the Page Load event. Instead, try moving your logic from CreateChildControls into a new method and call this method at the end of Page_Load.