Question

I have a boundfield in a gridview that programatically receives a hyperlink for the content in it. It gets a new dataset after a drop down list index change. One of the columns of the dataset will apply links to fields with data and skip those without, you can see my logic for applying links below:

if (e.Row.DataItem != null && int.TryParse(e.Row.Cells[4].Text, out incidents))
{
  HyperLink incidentsLink = new HyperLink();
  incidentsLink.ForeColor = System.Drawing.Color.Blue;
  incidentsLink.NavigateUrl = "~/somesite.aspx?no=" + stnNum + "&dt=" + date;
  incidentsLink.Text = e.Row.Cells[4].Text;
  e.Row.Cells[4].Controls.Add(incidentsLink);
}

This is applied OnRowDataBound for the gridview. Then I have another gridview that is wired to another drop down list. When either drop down list changes index it grabs a new dataset for the related gridview and fires a ajax update using an update panel.

What happens is when the second gridview updates it erases the links in the first gridview. It doesn’t erase the text, that stays, but the text is no longer anchored to a link. All links made this way and put into gridviews lose their link properties, however fields created using asp:HyperLinkField are left unchanged. The problem is that stnNum and date are not a part of the dataset that is returned for the first gridview, so I have to add them as a link after the gridview is already built.

The only solution I can think of is to refire the function that adds links to the gridview each time the second gridview updates. Any other solutions would be helpful, or an explanation as to why my link is being erased would be great.

Answer 1

Try binding the GridView/DropDowns only if there is not any POSTBACK. I believe POST Back event is letting your gridview & Controls to loose their data somehow.

protected void Page_Load(object sender, EventArgs e)
{
    if (!IsPostBack)
    {
    // Bind your Grids & Dropdowns here on page load
    }
}