dear all i am having problem inside update pannel there is a fileupload and upload button in my task when click on button this uploaded image show in asp image controlthis code is working fine with out update panel but inside update pannel button is not responding any click this
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design code below
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<asp:ScriptManager ID="ScriptManager1" runat="server"></asp:ScriptManager>
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>
<div class='col-sm-1' style="padding-top: 23px;">
<div class='form-group'>
<asp:Button ID="btnupload" runat="server" class='btn btn-info' Text="Upload" OnClick="btnupload_Click"/>
</div>
</div>
<div class="col-md-2">
<asp:Image ID="imgUser" ImageUrl="~/Images/avatar.png" class="img-circle img-responsive" runat="server" />
</div>
</ContentTemplate>
</asp:UpdatePanel>
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c# code
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protected void btnupload_Click(object sender, EventArgs e)
{
System.IO.Stream fs = FileUploadPic.PostedFile.InputStream;
System.IO.BinaryReader br = new System.IO.BinaryReader(fs);
Byte[] bytes = br.ReadBytes((Int32)fs.Length);
string base64String = Convert.ToBase64String(bytes, 0, bytes.Length);
imgUser.ImageUrl = "data:image/png;base64," + base64String;
DataUtility.SendAlert("hello");
}