问题
I have an UpdatePanel with a Label which I would like to update in my MasterPage. The event is taking place from my Content page and here are the codes.
Content ASP.net code:
<%@ MasterType TypeName="OnBoarding.Pages.Site" %>
<asp:DropDownList ID="ddlTaskName" CssClass="chosen-select" DataSourceID="dsPopulateTaskName" AutoPostBack="true" DataValueField="Task Name" runat="server" Width="100%" Font-Size="11px" AppendDataBoundItems="true" OnSelectedIndexChanged="ddlTaskName_onSelectIndexChanged">
<asp:ListItem Text="All" Value="%"></asp:ListItem>
</asp:DropDownList>
<asp:SqlDataSource ID="dsPopulateTaskName" runat="server" ConnectionString="<%$ ConnectionStrings:gvConnString %>" SelectCommand="QUERY"></asp:SqlDataSource>
C# code-behind:
protected void ddlTaskName_onSelectIndexChanged(object sender, EventArgs e)
{
FilterMessages();
}
public void FilterMessages()
{
DataTable msgTable = HttpContext.Current.Session["MessageTable"] as DataTable;
string query = "";
Stack msgStack = new Stack();
if (ddlClient.SelectedIndex > 0)
{
query += "Client = '" + ddlClient.SelectedItem.Text + "' OR Client is NULL";
}
if (ddlSite.SelectedIndex > 0 && query == "")
{
query += "Site = '" + ddlSite.SelectedItem.Text + "' OR Site is NULL";
}
else if (ddlSite.SelectedIndex > 0)
{
query += " AND Site = '" + ddlSite.SelectedItem.Text + "' OR Site is NULL";
}
if (ddlProvider.SelectedIndex > 0 && query == "")
{
query += "Provider = '" + ddlProvider.SelectedItem.Text + "' OR Provider is NULL";
}
else if (ddlProvider.SelectedIndex > 0)
{
query += " AND Provider = '" + ddlProvider.SelectedItem.Text + "' OR Provider is NULL";
}
UpdatePanel upMsg = (UpdatePanel)Master.FindControl("upMessage");
if (query != "")
{
DataRow[] result = msgTable.Select(query);
System.Web.UI.WebControls.Label lblMsg = (System.Web.UI.WebControls.Label)Master.FindControl("lblMessage");
if (lblMsg != null)
{
lblMsg.Text = "";
}
//lblMessage.Text = "";
foreach (DataRow row in result)
{
if (row["Active"].ToString() == "True")
{
string[] myStrings = new string[] { row["Created"].ToString().Split(' ')[0], string.IsNullOrEmpty(row["Client"].ToString()) ? null : row["Client"].ToString(), string.IsNullOrEmpty(row["Site"].ToString()) ? null : row["Site"].ToString(), row["Message"].ToString() };
string strResult = string.Join(" ", myStrings.Where(str => !string.IsNullOrEmpty(str)));
msgStack.Push(strResult);
}
}
foreach (string message in msgStack)
{
lblMsg.Text += message + "</br>";
//lblMessage.Text += message + "</br>";
}
}
else
{
PopulateMessageGV();
}
if (upMsg != null)
{
upMsg.Update();
}
//upMessage.Update();
}
protected void PopulateMessageGV()
{
UpdatePanel upMsg = (UpdatePanel)Master.FindControl("upMessage");
System.Web.UI.WebControls.Label lblMsg = (System.Web.UI.WebControls.Label)Master.FindControl("lblMessage");
if (lblMsg != null)
{
lblMsg.Text = "";
}
//lblMessage.Text = "";
DataTable dt = new DataTable();
dt.Columns.Add("ID", typeof(int));
dt.Columns.Add("Created", typeof(string));
dt.Columns.Add("Message", typeof(string));
dt.Columns.Add("Client", typeof(string));
dt.Columns.Add("Site", typeof(string));
dt.Columns.Add("Provider", typeof(string));
dt.Columns.Add("Active", typeof(bool));
dt.Columns.Add("CreatedBy", typeof(string));
using (var context = new ClientContext(hostWeb))
{
Stack msgStack = new Stack();
var hostSite = context.Web;
context.Load(hostSite, s => s.Title);
context.ExecuteQuery();
ListCollection allLists = hostSite.Lists;
Microsoft.SharePoint.Client.List messageList = allLists.GetByTitle("AdminMessage");
context.Load(messageList);
context.ExecuteQuery();
try
{
var query = CamlQuery.CreateAllItemsQuery();
Microsoft.SharePoint.Client.ListItemCollection allItems = messageList.GetItems(query);
context.Load(allItems);
context.ExecuteQuery();
if (allItems.Count > 0)
{
foreach (Microsoft.SharePoint.Client.ListItem item in allItems)
{
DataRow dr = dt.NewRow();
dr["ID"] = item["ID"];
dr["Created"] = item["Created"];
dr["Message"] = item["Message"];
dr["Client"] = item["Client"];
dr["Site"] = item["Site"];
dr["Provider"] = item["Provider"];
dr["Active"] = item["Active"];
FieldUserValue test = (FieldUserValue)item["Author"];
dr["CreatedBy"] = test.LookupValue.ToString();
dt.Rows.Add(dr);
if (item["Active"].ToString() == "True")
{
string[] myStrings = new string[] { item["Created"].ToString().Split(' ')[0], string.IsNullOrEmpty(dr["Client"].ToString()) ? null : item["Client"].ToString(), string.IsNullOrEmpty(dr["Site"].ToString()) ? null : item["Site"].ToString(), item["Message"].ToString() };
string result = string.Join(" ", myStrings.Where(str => !string.IsNullOrEmpty(str)));
msgStack.Push(result);
}
}
}
HttpContext.Current.Session["MessageTable"] = dt;
foreach (string message in msgStack)
{
lblMsg.Text += message + "</br>";
//lblMessage.Text += message + "</br>";
}
if (upMsg != null)
{
upMsg.Update();
}
//upMessage.Update();
}
catch (Exception ex)
{
string error = ex.Message;
}
}
}
MasterPage ASP.net code:
<asp:UpdatePanel runat="server" ID="upMessage" ClientIDMode="Static" UpdateMode="Conditional">
<ContentTemplate>
<asp:Label ID="lblMessage" Font-Size="x-small" runat="server" Text="" ClientIDMode="Static"></asp:Label>
</ContentTemplate>
</asp:UpdatePanel>
When I change the DropDown option the UpdatePanel in the masterpage doesn't update although putting a breakpoint there, shows that it is being hit.
How do I resolve the issue?
回答1:
Basically, you want to expose Public Property from MasterPage. Then access it from ContentPage.
Master Page
<%@ Master Language="C#" AutoEventWireup="true"
CodeBehind="Site.Master.cs" Inherits="DemoWebForm.Site" %>
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<body>
<form id="form1" runat="server">
<asp:Label runat="server" ID="MessageLabel" />
<asp:ContentPlaceHolder ID="MainContent" runat="server">
</asp:ContentPlaceHolder>
</form>
</body>
</html>
public partial class Site : System.Web.UI.MasterPage
{
public string MessageLabelText
{
get { return MessageLabel.Text; }
set { MessageLabel.Text = value; }
}
}
Content Page
<%@ Page Title="Home Page" Language="C#"
MasterPageFile="~/Site.Master"
AutoEventWireup="true"
CodeBehind="Default.aspx.cs" Inherits="DemoWebForm._Default" %>
<asp:Content ID="BodyContent" ContentPlaceHolderID="MainContent" runat="server">
<asp:DropDownList ID="TaskNameDropDownList"
runat="server"
AutoPostBack="True"
OnSelectedIndexChanged="TaskNameDropDownList_SelectedIndexChanged">
<asp:ListItem Text="One" Value="1" />
<asp:ListItem Text="Two" Value="2" />
</asp:DropDownList>
</asp:Content>
public partial class _Default : Page
{
protected void TaskNameDropDownList_SelectedIndexChanged(
object sender, EventArgs e)
{
var master = Master as Site;
if (master != null)
{
master.MessageLabelText = TaskNameDropDownList.SelectedValue;
}
}
}
来源：https://stackoverflow.com/questions/25513337/update-masterpage-control-from-content-page