如何在asp.net c下拉列表中绑定工具提示＃

Question

I want to bind tool tip to drop down list item. My code is

protected void ddl_DataBound(object sender, EventArgs e)
{
    if (ViewState["HeadToolTip"] != null)
    {
        DataTable dt = ViewState["HeadToolTip"] as DataTable;
        DropDownList ddl = sender as DropDownList;
        if (ddl != null)
        {
            foreach (ListItem li in ddl.Items)
            {

                DataRow drow = dt.Rows.Cast<DataRow>().FirstOrDefault(x => x.Field<string>("HeadCode") == li.Value.ToString());
                if (drow != null)
                {
                    li.Attributes["title"] = drow["ToolTip"].ToString();// li.Text;
                }
            }
        }
    }
}

It is working but after selection of any item tool tip is removed from all item list.

Answer 1

You are setting tooltip on DataBound , it might be possible when you are not binding Data within Load or SelectedIndexChange , when you select an item, 2 things occur, SelectedIndexChange event fires and then Page_Load event fires, you are not binding in either one of them I think. That's why somehow, tooltip not working. You should place your tooltip code within a function and call that function from Page_Load or SelectedIndexChange , so the tooltip will again be binded with DropDownList

Hope it solves your issue. Regards!