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Interacting Between RadAjaxPanels

This help article features a code example that shows how to interact between two RadAjaxPanel controls without using a RadAjaxManager. Telerik recommends using a RadAjaxManager and the technique discussed in this article, while possible, is not supported.

Telerik designed the RadAjaxPanel control to update only its content controls, so Telerik Support always recommends that you use RadAjaxManager when you need to update external controls.

However, you can achieve interaction between panels without the use of RadAjaxManager . The example bellow demonstrate a technique using the ResponseScripts property, together with the client-side ajaxRequest() function. Note the use of Page_PreRender event as well as the property persisted in ViewState.

The following example demonstrates how to handle an AJAX request from one RadAjaxPanel and how to initiate AJAX request from the RadAjaxPanel we want to update.

<telerik:RadScriptManager ID="RadScriptManager1" runat="server">
<telerik:RadAjaxPanel ID="RadAjaxPanel1" runat="server">
<asp:Button ID="btnIncrease" OnClick="btnIncrease_Click" Text="Increase" runat="server">
<asp:Label ID="Label1" runat="server">0</asp:Label>
<asp:TextBox ID="TextBox1" Text="0" runat="server"></asp:TextBox>
<telerik:RadAjaxPanel ID="RadAjaxPanel2" runat="server">
<asp:Button ID="btnDecrease" OnClick="btnDecrease_Click" Text="Decrease" runat="server">
<asp:Label ID="Label2" runat="server">0</asp:Label>
<asp:TextBox ID="TextBox2" Text="0" runat="server"></asp:TextBox>

And in the code-behind:

protected void Page_PreRender(object sender, EventArgs e)
            if (RadAjaxPanel1.IsAjaxRequest || RadAjaxPanel2.IsAjaxRequest)
                TextBox1.Text = Label1.Text = TextBox2.Text = Label2.Text = Count.ToString();
public int Count
                return this.ViewState["Count"] == null ? 0 : (int)this.ViewState["Count"];
                this.ViewState["Count"] = value;
protected void btnIncrease_Click(object sender, System.EventArgs e)
            RadAjaxPanel1.ResponseScripts.Add(String.Format("$find('{0}').ajaxRequest();", RadAjaxPanel2.ClientID));
protected void btnDecrease_Click(object sender, System.EventArgs e)
            RadAjaxPanel2.ResponseScripts.Add(String.Format("$find('{0}').ajaxRequest();", RadAjaxPanel1.ClientID));
Protected Sub Page_PreRender(ByVal sender As Object, ByVal e As EventArgs) Handles Me.PreRender
            If RadAjaxPanel1.IsAjaxRequest Or RadAjaxPanel2.IsAjaxRequest Then
                Dim countValue As String = Count.ToString()
                TextBox1.Text = countValue
                Label1.Text = countValue
                TextBox2.Text = countValue
                Label2.Text = countValue
            End If
End Sub 'Page_PreRender

Public Property Count() As Integer
                If Me.ViewState("Count") Is Nothing Then
                    Return 0
                    Return CInt(Me.ViewState("Count"))
                End If
            End Get
            Set(ByVal value As Integer)
                Me.ViewState("Count") = value
            End Set
End Property

Protected Sub btnIncrease_Click(ByVal sender As Object, ByVal e As System.EventArgs)
            Count += 1
            RadAjaxPanel1.ResponseScripts.Add(String.Format("$find('{0}').ajaxRequest();", RadAjaxPanel2.ClientID))
End Sub 'btnIncrease_Click

Protected Sub btnDecrease_Click(ByVal sender As Object, ByVal e As System.EventArgs)
            Count -= 1
            RadAjaxPanel2.ResponseScripts.Add(String.Format("$find('{0}').ajaxRequest();", RadAjaxPanel1.ClientID))
End Sub 'btnDecrease_Click 
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