How to refresh 2 repeater in asp.net - asp.net

Question

I'm building a social network in asp. I code main page has post status and comment after each status using repeater control, but when I click on 'Post' button and 'Comment' button the repeater control not refresh. I mush logout and login again to display new status and new comment. How can I solve this problem:
MainPage.aspx
<asp:Content runat="server" ID="BodyContent" ContentPlaceHolderID="MainContent">
<h2>Hello</h2>
<asp:Label ID="lblUser" runat="server" Text=""></asp:Label>
<asp:Label ID="lblID" runat="server" Text=""></asp:Label>
<hr />
<asp:TextBox ID="txtMessage" runat="server" TextMode="MultiLine"></asp:TextBox>
<asp:Button ID="btnPost" runat="server" Text="Post" OnClick="btnPost_Click" />
<hr />
<asp:Repeater ID="repeater" runat="server" OnItemDataBound="repeater_ItemDataBound">
<HeaderTemplate>
<ul>
</HeaderTemplate>
<FooterTemplate>
</ul>
</FooterTemplate>
<ItemTemplate>
<asp:Label ID="labelID" runat="server" Text='<%#DataBinder.Eval(Container.DataItem, "Mess_Id") %>'></asp:Label>
<li><%#DataBinder.Eval(Container.DataItem, "Message")%></li>
<asp:Repeater ID="repeatComment" runat="server">
<HeaderTemplate>
<ul>
</HeaderTemplate>
<FooterTemplate>
</ul>
</FooterTemplate>
<ItemTemplate>
<li>
<%#DataBinder.Eval(Container.DataItem, "Comments")%>
</li>
</ItemTemplate>
</asp:Repeater>
<br />
<asp:TextBox ID="txtComment" runat="server"></asp:TextBox>
<asp:Button ID="btnComment" runat="server" Text="Comment" OnClick="btnComment_Click" />
<br />
</ItemTemplate>
</asp:Repeater>
MainPage.aspx.cs
private List<Message> list;
private ESupervisionEntities db;
private MessageController message;
int id;
private System.Web.UI.WebControls.Repeater repeatComment;
protected void Page_Load(object sender, EventArgs e)
{
if (Session["USER_NAME"] != null)
{
lblUser.Text = Session["USER_NAME"].ToString();
lblID.Text = Session["USER_ID"].ToString();
}
if (!IsPostBack)
{
db = new ESupervisionEntities();
message = new MessageController();
id = Int32.Parse(lblID.Text);
list = message.getAllMyByID(db, id, 2);
repeater.DataSource = list;
repeater.DataBind();
}
}
protected void repeater_ItemDataBound(object sender, RepeaterItemEventArgs e)
{
RepeaterItem item = e.Item;
if ((item.ItemType == ListItemType.Item) ||
(item.ItemType == ListItemType.AlternatingItem))
{
repeatComment = (Repeater)item.FindControl("repeatComment");
var myLabel = e.Item.FindControl("labelID") as Label;
int num = Int32.Parse(myLabel.Text);
List<MessComment> lst = message.getAllCommentByID(db, id, num);
repeatComment.DataSource = lst;
repeatComment.DataBind();
}
}
protected void btnPost_Click(object sender, EventArgs e)
{
db = new ESupervisionEntities();
message = new MessageController();
id = Int32.Parse(lblID.Text);
message.createMess(db, id, 2, txtMessage.Text, true);
}
protected void btnComment_Click(object sender, EventArgs e) {
var btn = (Button)sender;
var item = (RepeaterItem)btn.NamingContainer;
Button comment = (Button)item.FindControl("btnComment");
TextBox txtComment = (TextBox)item.FindControl("txtComment");
Label msgID = (Label)item.FindControl("labelID");
db = new ESupervisionEntities();
message = new MessageController();
id = Int32.Parse(lblID.Text);
message.createComment(db, int.Parse(msgID.Text), id, 2, txtComment.Text, true);
}

Answer 1

Try this code...
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
BindData();
}
private void BindData()
{
db = new ESupervisionEntities();
message = new MessageController();
id = Int32.Parse(lblID.Text);
list = message.getAllMyByID(db, id, 2);
repeater.DataSource = list;
repeater.DataBind();
}
protected void btnPost_Click(object sender, EventArgs e)
{
db = new ESupervisionEntities();
message = new MessageController();
id = Int32.Parse(lblID.Text);
message.createMess(db, id, 2, txtMessage.Text, true);
BindData();
}
protected void btnComment_Click(object sender, EventArgs e)
{
var btn = (Button)sender;
var item = (RepeaterItem)btn.NamingContainer;
Button comment = (Button)item.FindControl("btnComment");
TextBox txtComment = (TextBox)item.FindControl("txtComment");
Label msgID = (Label)item.FindControl("labelID");
db = new ESupervisionEntities();
message = new MessageController();
id = Int32.Parse(lblID.Text);
message.createComment(db, int.Parse(msgID.Text), id, 2, txtComment.Text, true);
BindData();
}